Hegseth says that in the Indian Ocean, the US sank "an Iranian warship that thought it was safe in international waters".

"Instead it was sunk by a torpedo," he says.

Hegseth did not name the Iranian ship that was attacked.

But earlier the Sri Lankan navy reported the Iris Dena went down in the Indian Ocean, with around 140 people on board missing.

This "was never meant to be a fair fight, and it's not a fair fight", says Hegseth, adding that the US is punching Iran "while they're down".

"More and larger waves are coming, we are just getting started," he says.

Hegseth says the results over the past four days have been "incredible, historic really".

"They are toast, and they know it," he says referring to the Iranian regime.

He adds that US forces have begun to "hunt, dismantle, demoralise, destroy and defeat" the regime's capabilities.

He says that Iranian leaders will be looking up and seeing only "US and Israeli air power" until US and Israel decide the war is over.

Image source, Pool

The Pentagon briefing has started.

US Secretary of Defense Pete Hegseth says: "America is winning, decisively, devastatingly and without mercy."

"We are only four days in", he says, but "as Trump has said" the US "will take all the time we need" to make sure the operation is a success.

Tom Bateman
US State Department correspondent, reporting from the Pentagon

I’m in the Pentagon in the press briefing room where two podiums are set up for Defense Secretary Pete Hegseth and the Chair of the Joint Chiefs Gen Dan Caine.

This is the second time they’ve given a news briefing since the US and Israel launched their attack on Iran.

The room is full, although the front rows seem to have been largely reserved for the Pentagon’s new resident press corps.

Much of the traditional US media lost their continuing access to the Pentagon last year after refusing to sign up to new rules that threatened expulsion if journalists reported on any information that hadn’t been officially approved - though it looks like they’re being granted access for these one off press conferences.

We’re expecting Hegseth and Caine in the next few minutes.

We're expecting to hear from US Secretary of Defense Pete Hegseth very shortly, with an update on the war on Iran from the Pentagon.

We'll be bringing you coverage in the live stream at the top of this page.

The UK Maritime Trade Operations (UKMTO) says it has received a report of a container ship being hit by an "unknown projectile" off Oman's north coast today in the Straits of Hormuz.

The ship reported that the strike had caused a fire in its engine room, but no environmental impact had been reported. Authorities are continuing to investigate.

Image source, UK Maritime Trade Operations

Let's go back now to the Iranian navy ship that sank off the coast of Sri Lanka. As a reminder, around 140 people are missing, but the cause of the sinking is not known.

The BBC's Sinhala team spoke to the Sri Lankan navy about the condition of the ship.

"When we received the distress signal and our navy vessels went to the scene of the incident, we only saw a few lifeboats," the spokesman says.

"There was no Iranian ship in sight. It had sunk."

Image source, Reuters

Verified image shows strike in eastern Tehranpublished at 12:24 GMT 4 March

12:24 GMT 4 March

By Yi Ma and Ghoncheh Habibiazad

A new image showing a large plume of black smoke rising in eastern Tehran after an apparent air strike has been verified.

BBC Verify was able to locate where the picture, which first appeared online earlier today, was taken by identifying the minarets in the foreground on street view and satellite imagery.

We can confirm the explosion took place several streets away from the Hassani Mosque.

It is not clear what was hit or if there were any casualties.

Image source, Telegram

Freya Scott-Turner
Live reporter

Image source, EPA/Shutterstock

Missiles continue to fly across the Middle East, as the war spills into its fifth day.

Latest across the region:

• Around 140 people are thought to be missing as Sri Lanka's navy has confirmed that it’s rescued 32 people after it received a distress call from Iranian navy ship Iris Dena early on Wednesday morning. The cause is currently unknown
• Israel launched a fresh wave of strikes across the region, with several people reportedly killed in attacks on Lebanon that the IDF says were targeting Hezbollah operatives and facilities. The army is now ordering civilians in southern Lebanon to leave "immediately" ahead of military action
• In Tehran, many buildings have been reduced to rubble - while "security headquarters" there were also struck in overnight attacks, according to the Israeli military
• New footage shows the US consulate in Dubai on fire after an apparent Iranian drone strike on Tuesday, while a US air base in Qatar was struck by an Iranian missile

On the ground in Iran:

• A three-day funeral for late Ayatollah Khamenei - killed in an Israeli attack on Saturday - that was due to start today has been "postponed", Iranian state media reports
• Speculation is mounting over who will replace the supreme leader, as two Iranian sources tell Reuters that his son Mojtaba Khamenei has survived attacks
• "It's getting worse every day", an Iranian man tells the BBC, as a US-based Human Rights Activist News Agency says that at least 1,097 civilians have been killed there since the US-Israel attacks began on Saturday

Evacuation efforts continue:

• With significant flight disruption, countries are working to evacuate citizens who want to leave out of the Middle East. The first flight specifically arranged by the UK government is scheduled to leave Muscat International Airport at 23:00 local time (19:00 GMT) today

Nato air defences have destroyed an Iranian missile heading towards Turkish airspace, according to Turkey's defence ministry.

In a statement, originally in Turkish, the defence ministry says there are no casualties or injuries.

It says the missile was "detected passing through Iraqi and Syrian airspace and heading towards Turkish airspace".

"We warn all parties to refrain from taking any steps that could cause the conflict to spread further in the region," the statement from Turkey, a member of Nato, says.

Yogita Limaye
South Asia correspondent, reporting from Mumbai

Sri Lanka’s navy has confirmed that it’s rescued 32 people after it received a distress call from Iranian navy ship Iris Dena early on Tuesday.

Budhika Sampath, the spokesman of Sri Lanka’s navy says: “Though it was beyond our waters, it was within our search and rescue region. So we were obliged to respond as per international obligations.”

He adds: “We found people floating on the water, rescued them, and later when we inquired we found that those people are from an Iranian ship.”

He also says that according to the documentation of the ship 180 people are believed to have been on board, although the exact number of missing is unknown.

The spokesman says at the time of launching the rescue operations they did not see the vessel but saw oil patches on the water and floating life rafts.

He also tells the BBC that he rejects the reports of a submarine attack causing the sinking, and that the cause is unknown.

Earlier the secretary of the country’s defence ministry Air Vice Marshal Sampath Thuiyakontha told BBC Sinhala that around 140 people are thought to be missing.

So far, Sri Lanka’s military has not been able to confirm what might have caused the ship to sink.

Image source, Reuters

Nick Johnson
Reporting from Gosport

Image source, PA Media

I’m aboard Gosport Boat Yard’s African Grey - getting a closer look at preparations for HMS Dragon’s voyage to the Mediterranean.

The destroyer is docked by a pontoon, after being moved from a permanent mooring last night.

It’s here to take on ammunition before beginning a journey to the eastern Mediterranean.

HMS Dragon is being sent there for defensive purposes, but she is also having a significant amount of her own firepower loaded aboard. That includes missile batteries - one fires around eight missiles in 10 seconds.

There's a crew of more than 200, and I can see some of those personnel walking from the ship to the pontoon.

When she does eventually set sail, it could take up to a week until she reaches Cyprus.

The state funeral for Iran's Supreme Leader Ayatollah Ali Khamenei's has been postponed, according to reports in Iranian state media.

The three-day funeral was due to begin later today, with images on social media that showed preparations to get everything in place.

However, reports suggest that organisers have said that the ceremony will be postponed until there is infrastructure in place.

No date for when the ceremony will take place has been announced.

Here's a look at images taken today in the Iranian capital Tehran showing the extent of the damage caused by days of US-Israeli strikes:

Image source, EPA

Image source, EPA

Image source, EPA

Image source, Reuters

Image source, EPA

The Israel Defense Forces (IDF) has told civilians living south of Lebanon's Litani river to head north of the river immediately ahead of "military action" against Hezbollah in the area.

"For your own protection, you must vacate your homes immediately," warns the IDF.

In a statement, it says anyone located near "Hezbollah operatives, facilities, or weapon is putting their life at risk".

"Any building or home utilized by Hezbollah for military purposes is a legitimate target and may be engaged," the statement says.

Alice Cuddy
Reporting from Hazmieh

Image source, Alice Cuddy/BBC

I’m in Hazmieh - on the outskirts of the Lebanese capital Beirut - where a hotel was struck overnight.

The Comfort Hotel sustained serious damage to its first and second floors, and witnesses say the receptionist was seriously injured and taken to hospital.

A clean-up effort was under way this morning as locals looked on in shock. "We woke up to an explosion and dust," one man who had been staying at the hotel says. "We don't know anything. We don't know what happened... This area is normally secure."

Magay Chebli, who owns the hotel with her husband, says she received a call at about 4am, telling her the hotel had been hit in an Israeli strike.

She says displaced people had been among those staying at the hotel, and that they had tried to take in only families.

"I wish you were here before and you saw how they [the families] were coming out with their diapers and milk. We don't have terrorists here. We hate them," she says.

The BBC has asked the Israeli military about the strike and what the target was. Magay says she no longer feels safe anywhere in Lebanon but will not leave.

"Who do I trust? Should I trust Hezbollah or Israel? I don't trust anyone," she says.

As the cleanup happened at the hotel in Hazmieh, explosions from Israeli strikes this morning could be heard in the southern suburbs of Dahieh.

Image source, Alice Cuddy/BBC

Jessica Parker
Reporting from Cyprus

We’ve spotted what we believe to be a Greek frigate just outside the Cypriot port of Limassol.

It’s one of two medium-sized warships sent by Athens to support Cyprus after a drone hit a British air base on the Mediterranean island.

Greek, French and British military assets are being deployed to help with counter-drone operations.

But British destroyer HMS Dragon has yet to leave Portsmouth and will likely take the best part of a week to get here.

There has been an attempted drone attack on a major oil refinery in Saudi Arabia, the Saudi defence ministry says.

The attack was attempted on Ras Tanura oil refinery - thought to be the biggest in Saudi Arabia.

"Initial estimates indicate that the attack was carried out by a drone and did not result in any damage," the defence ministry says.

The refinery was previously hit by an Iranian attack - as the satellite image below, taken on Monday, shows.

Image source, Vantor

Jon Donnison
Reporting from Metula

From the small Israeli town of Metula right on the border with Lebanon, you can hear what sounds like a full-on gun battle just a kilometre (0.6 miles) or so away.

For 10 minutes heavy bursts of machine gun fire echoed across the valley, interspersed with what sounded like artillery fire. The Israeli army says it is trying to push Hezbollah fighters - supported by Iran - back from the south of Lebanon.

Dozens of Lebanese villages were flattened in the war between Israel and Hezbollah in 2024. Many of the group’s underground bunkers have been destroyed.

But Hezbollah are clearly still there and putting up a fight.