We're moving our live coveragepublished at 01:34 BST 4 April
We have moved our live coverage here, and will continue to bring you the latest developments from the war in the Middle East, as the conflict nears the end of its fifth week.
One crew member from a US fighter jet downed in Iran has been rescued, US media report
Earlier, two sources told the BBC's US partner CBS News that a search and rescue effort was under way for a downed US F-15 fighter jet in southern Iran. It's not known what has happened to the second crew member
Two other American aircraft came under fire while trying to rescue the F-15 pilots, CBS also reports, including an A-10 Warthog and a helicopter
BBC Verify has confirmed a video showing what appears to be a US plane accompanied by two helicopters flying over Khuzestan province - Iran's state media claim Iranian forces shot down the plane
It's the first known case of a US fighter jet being shot down over Iran during this conflict, our foreign correspondent writes, and comes after Trump claimed Iran "can't do a thing" about US planes flying over it
Meanwhile, Prime Minister Benjamin Netanyahu claims Israeli strikes have destroyed 70% of Iran's steel production capacity - and says Israel and the US will continue to "crush" the country
Edited by Christal Hayes and Alys Davies, with reporting from BBC Persian and teams across the Middle East
We have moved our live coverage here, and will continue to bring you the latest developments from the war in the Middle East, as the conflict nears the end of its fifth week.
A US fighter jet downed by enemy forces has been an exceptionally rare occurrence in the last few decades.
Three US F-15 fighter jets were downed over Kuwait in "an apparent friendly fire incident," in early March, US Central Command (CentCom) said. All six crew members were able to safely eject.
All six crew members of a US military refuelling aircraft were killed in an incident involving a second aircraft on March 12 in western Iraq, CentCom also said.
On 7 April 2003, a US F-15E Strike Eagle was downed over Iraq during Operation Iraqi Freedom, killing pilot Eric Das and weapons officer William Watkins.
The flight took off from Al Udeid Air Base, in Qatar, to perform a “critical interdiction mission”, attacking targets near Tikrit, Iraq, according to the US Navy Memorial website.
A US A-10 Thunderbolt II plane is also believed to have been shot down by a surface-to-air missile in Baghdad, Iraq, on 8 April 2003, according to the US air force. The pilot safely ejected before the aircraft crashed.
Another F-15E fighter jet crashed in northeast Libya in March 2011. Four aircraft and two helicopters were sent to recover the pilot, the US Marine Corps said at the time.
Ghoncheh Habibiazad
Senior reporter, BBC Persian
The deputy governor of Iran’s southern Kohgiluyeh-Boyerahmad province has said that despite “extensive efforts" by the US using fighter jets and helicopters, search operations for the “missing pilot” of the downed F-15 fighter jet are still continuing with “full force”.
According a report by Iran's semi-official Fars news agency, the deputy is saying that “efforts by police, security forces and local people to identify and apprehend the pilot are still ongoing” and is asking people to contact the authorities in case they find any information about the “missing pilot”.
While we don’t know exactly where the jet was downed, there are names of two provinces mentioned frequently on Iran’s state media so far - Kohgiluyeh-Boyerahmad and Khuzestan.
Jacob Phillips
Live reporter
A search and rescue mission has rescued a crew member from a US F-15E fighter jet that was downed in southern Iran, US media reports.
What has happened to the second crew member on the jet remains unknown, but CBS reports that the search is ongoing, citing two officials.
It says the rescue crew included two helicopters and an A-10 Warthog plane. It adds one helicopter carrying the rescued pilot from the F-15 jet was hit by small arms fire, injuring crew members on board - but it landed safely.
CBS reports that the A-10 Warthog was hit, with the pilot ejecting over the Gulf and subsequently rescued. Iran's army claims to have shot down an A-10 Warthog, according to state media reports - it's not clear if this is the same plane that CBS was reporting about.
Verified footage appears to show a US plane and two helicopters searching for the fighter jet's crew in the Khuzestan province.
There have also been reports that the Israeli military has held off strikes in the area, while the search operation is being undertaken.
US President Donald Trump told US network NBC "we're in war", and the attack on the fighter jet will not affect any negotiations with Iran.
Image source, State mediaBBC Verify has spoken to experts who confirmed the debris shared in pictures on social media has come from a US F-15E Strike Eagle
Bernd Debusmann Jr
White House reporter
Image source, Getty ImagesUS Air Force pararescue units train extensively to recover downed aircrew behind enemy lines
The search for one missing US service member after a fighter jet came down in Iran is ongoing, according to CBS, the BBC's US partner.
In the US, elite units of the Air Force are specially trained for combat search and rescue (CSAR) missions and are often pre-emptively deployed near conflict areas where aircraft could be lost. It's not clear if these are the forces deployed in this specific search and rescue operation.
Their work is considered part of a broader promise to US service members that they will not be left behind.
The missions are extremely time-sensitive, as enemy forces would likely be deployed in the same area to try and locate the same US personnel the CSAR teams are trying to rescue.
Modern CSAR began during the Vietnam War and required a vast expansion of rescue missions with increased scope and complexity.
The experience helped the military refine tactics and procedures that have helped form the foundation of rescue operations since.
Bernd Debusmann Jr
White House reporter
Image source, EPA/ShutterstockUS military personnel on patrol as a US Air Force B-1 bomber gets prepared for operation at an airbase in the UK
With the US-Israeli war with Iran waging on, the White House earlier announced that it will ask the US Congress to approve $1.5tn (£1.13tn) defence budget for the 2027 fiscal year - a record-breaking 42% increase from the year before.
If approved and enacted by Congress, the budget would be the highest in modern US history.
Trump's move to up defence spending, however, pre-dates the beginning of the current conflict in Iran, and is reflective of the Trump administration's focus on domestic production and high-profile projects.
This includes funding his proposed Golden Dome missile defence system, which is aimed at protecting the US from next-generation aerial threats.
An outline of the budget shared by the Office of Management and Budget notes that the request would cover dozen of military ships, including a new series of heavily armed US Navy Trump-class battleships that the US president unveiled in December.
The request is separate from one made in March that was specifically tied to the war in Iran, in which the Pentagon proposed $200bn to support the ongoing Operation Epic Fury and to backfill munitions and supplies.
Grace Eliza Goodwin
US reporter
I've spoken to two military analysts who say that while a US fighter jet being shot down over Iran is operationally not very significant, it could further galvanise the American public against the war.
"For people who have been arguing from the start that this war was a mistake, that this war was an unnecessary risk to US service members, it was an unnecessary use of US military power and a waste of US military resources - this is just the exclamation point on that argument," says Jennifer Kavanagh, a senior fellow and director of military analysis at the think tank Defense Priorities, which advocates for restraint in US foreign policy.
She says the incident makes walking away from the war now, at least in the immediate term, "essentially impossible politically for Trump".
That's because, she says, the US president needs something else to further underline his claims of victory and "this is not it".
James Jeffrey, a military strategy expert and fellow at think tank The Washington Institute, says most Americans would say right now this incident makes them more upset about the war.
"This is really a concern because that's how they feel," Jeffrey says. "Americans love their service people, more than most modern countries do."
But, he says, public concern won't affect how Trump handles the war, or what steps he decides to take next.
Image source, ReutersPresident Donald Trump says the downing of a US fighter jet would not impact any negotiations with Iran to end the war, according to NBC News.
It says in a brief phone interview the president was asked if today’s events would have an impact. He replied: "No, not at all. No, it’s war. We’re in war."
Ione Wells
Foreign correspondent
According to CBS reporting, citing two US officials, the fallout from this incident is worse than initially thought.
Not only did they say an F-15E was shot down this morning, but an A-10 Warthog aircraft that was part of the search and rescue mission for the downed jet was also shot and damaged.
The pilot from that ejected and was successfully recovered.
Two helicopters also took part in the rescue mission and retrieved the F-15E pilot who had ejected, but the search is continuing for the second crew member.
The helicopter carrying the rescued pilot was then hit by small arms fire, wounding crew members on board.
All of this indicates that, despite Donald Trump’s recent claims that there is nothing Iran can do about US aircraft in its skies - the dangers still very much exist.
Ghoncheh Habibiazad
Senior reporter, BBC Persian
I'm hearing that there have been heavy explosions in east Tehran from two sources.
Three others say they're hearing fighter jets in the sky.
Iranian outlets say that air defences have been activated in the city.
Ghoncheh Habibiazad
Senior reporter, BBC Persian
Iran's state TV is reporting that "an American A10 aircraft was shot by the defence systems of the Army Air Defence Force and crashed in the Persian Gulf in southern Iran", citing the Iranian Army.
It adds that it was shot down hours ago around the Strait of Hormuz.
It's not clear if this is the same A-10 Warthog that the BBC's US partner CBS reports was hit during the search and rescue effort for the F-15E.
Two US aircraft involved in the rescue of the American F-15 fighter jet over Iran have also come under fire, according to two US officials speaking to CBS.
The BBC's US partner reports that an A-10 Warthog taking part in the search and rescue was hit, with the pilot ejecting over the Gulf, where he was rescued.

Two helicopters were also involved in the search, rescuing one of the two F-15E airmen from the earlier crash, CBS says, and the helicopter carrying a recovered pilot was hit by small arms fire, injuring crew members on board. The helicopter landed safely and the personnel are being treated.
CBS earlier reported that the F-15 was shot down early afternoon local time, but there have been conflicting reports about the timing.
The search is still reportedly under way for the second crew member, a weapon systems officer.
An Egyptian man has died during an evacuation after falling debris struck gas facilities, according to authorities in Abu Dhabi.
Two fires broke out at the Habshan gas facilities "following a successful interception" by air defence systems, the Abu Dhabi media office says.
An assessment is under way at the site, the office adds.
Ghoncheh Habibiazad
Senior reporter, BBC Persian
The death toll from strikes on Thursday on a bridge in Karaj - a city near Tehran in Alborz province - has risen to 13, according to Amirhossein Daneshkohan, Director General of the Alborz Foundation of Martyrs and Veterans Affairs in Iran.
Earlier today, we reported that the death toll was eight.
Daneshkohan said those killed were from “all walks of life”, including “municipal employees”.
Iranian media reported that 95 people were injured when the bridge under construction was bombed.
US President Donald Trump has warned Iran there will be strikes on its bridges and electric power plants if its leaders do not agree to his terms to end the war.
Israel's military has delayed strikes in the area of Iran where the search for missing US fighter jet crew is under way, according to reports from CNN, AP news agency and Israel's Channel 12.
CNN says an Israeli official told the network that strikes had been postponed in the search area, while Channel 12, citing a senior Israeli official, reported the strikes had been cancelled. AP also reported that air strikes had been halted in relevant areas due to the rescue efforts.
AP says the Israeli official spoke to them on condition of anonymity "because the operation is ongoing".
The Israel Defense Forces has not confirmed these reports.
Grace Eliza Goodwin
US reporter
I’ve just spoken to two military analysts, who say what’s most striking about Iran reportedly shooting down a US fighter jet is that it didn’t happen sooner.
“It was sort of inevitable,” says Jennifer Kavanagh, a senior fellow and director of military analysis at think tank Defense Priorities.
It was only “a matter of time before there was some incident like this”, she says.
“We know that Iran has anti-aircraft weapons, and the idea that they had all been eliminated was quite hard to believe and likely inaccurate from the start,” she adds.
US President Donald Trump has repeatedly said that Iran’s air capabilities have been obliterated.
James Jeffrey, a military strategy expert and fellow at think tank The Washington Institute, also says it’s “amazing” that this is the first fighter jet Iran reportedly shot down.
But both Jeffrey and Kavanagh say that, in the grand scheme of the war, this incident matters very little.
While it’s "a big victory" for Iran to have shot down an American jet, for the US, losing a single aircraft “isn’t going to change the operational outcome of the war,” Kavanagh says.
By Joshua Cheetham
BBC Verify has spoken to an expert who confirms that debris in images widely circulating on social media has come from a US F-15E Strike Eagle.
The piece shown are a wingtip and part of a vertical stabiliser from a plane from the US 494th Fighter Squadron based at RAF Lakenheath in the UK, according to Justin Bronk, senior research fellow for airpower and technology in the Military Sciences team at the Rusi think tank.
A reverse image search shows the images only began to circulate on social media today.
We cannot confirm where the images were taken as they are close-ups and there isn't a clear sign that lets us geolocate them, but we have checked them for AI and there are no signs of manipulation.
Image source, XThis image is one of many shared on social media which claims to show debris from a US fighter jet
Ghoncheh Habibiazad
Senior reporter, BBC Persian
While we don’t know exactly where the jet was downed, there are names of two provinces mentioned frequently on Iran’s state media so far - Khuzestan and Kohgiluyeh-Boyerahmad.
BBC Verify has confirmed that a video showing what appears to be a US plane accompanied by two helicopters flying over southern Iran was recorded in Khuzestan province.
Khuzestan is a core centre of Iran’s economy and a major powerhouse for oil and a number of other industries. The province is home to more than 4.7 million people.
Its major steel company was recently targeted during the war and shut down as the result of strikes.
Right next to Khuzestan is mountainous Kohgiluyeh - more than 700,000 are estimated to be living there.
Iranian news outlets have published a video claiming to show people there “searching for the American pilot”.
An Iranian state TV newsreader for a local channel has reported that rewards will be given to anyone who captures the pilot alive.

Information is still coming in after reports that a US fighter jet has been downed over Iranian territory.
What we know:
What we don't yet know:
As reports suggest a search and rescue operation is under way for a downed US F-15 fighter jet in southern Iran, fighting continues.
The Israel Defense Forces (IDF) says it has launched another wave of strikes in Tehran.
In the past 24 hours, it says it has carried out "more than 70 strikes in western and central Iran targeting ballistic missile launch sites and unmanned aerial vehicles".
In a separate update, the IDF says it has started striking parts of Beirut.
It also reports detecting multiple barrages of missiles fired at its territory from Iran throughout the day.