WASHINGTON • It started with eight helicopters flying low in the dark across hostile territory.

It ended two hours later with one of the most wanted men in the world cornered by US soldiers, then blowing himself up.

And thousands of miles away in the White House Situation Room, President Donald Trump said he witnessed Islamic State in Iraq and Syria (ISIS) leader Abu Bakr al-Baghdadi's end on video in amazement. "As though you were watching a movie," he said.

In extended questions and answers yesterday after announcing the raid, Mr Trump said that Baghdadi, 48, had been "under surveillance for a couple of weeks".

As soon as confirmation came in about his location, the raid by special forces swung into motion on Saturday.

"A large group" took part, with "eight helicopters and we had many other ships and planes", Mr Trump said.

First, they had to cross hostile territory from a still-undisclosed location into north-west Syria, flying about one hour and 10 minutes.

The operation was staged from a base in western Iraq, a United States official told Reuters.

Mr Trump said: "We flew very, very low and very, very fast. But it was a big - it was a very dangerous - part of the mission. Getting in and getting out.

"There was a chance that we would have met unbelievable fire."

And when they landed at the targeted compound, "all hell broke loose", according to Mr Trump.

"A large crew of brilliant fighters ran out of those helicopters and blew holes into the side of the building" to avoid booby traps in any doors.

That "was something really amazing to see", he said about his experience in the Situation Room, where he was joined by Vice-President Mike Pence and senior military and national security officers. "We watched it so clearly."

"They were greeted with a lot of firepower," he said. A "large number" of Baghdadi's supporters died in the return fire, Mr Trump said, but there were no US troop casualties.

Commanders relayed back their progress, step by step: Eleven children had been taken out alive, they said. Prisoners were being taken. Baghdadi's wives were dead.

And then came the call everyone was waiting for. "Sir, there's only one person in the building. We are sure he's in the tunnel trying to escape but it's a dead-end tunnel," Mr Trump recounted being told.

It was Baghdadi.

Knowing beforehand that there would be tunnels and that the fugitive was likely wearing a suicide vest, the US forces had taken along a robot. But it never got used.

"We were moving too fast," Mr Trump said. "They were chasing."

Baghdadi had taken three of his children down into the tunnel, the US President said. Their presence was not going to stop the inevitable, though.

"It was brutal," Mr Trump said.

The US troops sent dogs down the tunnel and the ISIS mastermind "blew himself up".

"He reached the end of the tunnel as our dogs chased him down. He ignited his vest, killing himself and the three children," Mr Trump said.

"He didn't die a hero, he died a coward, crying, whimpering and screaming and bringing three kids with him to die. Certain death. And he knew the tunnel had no end."

The US soldiers took samples from the mutilated leader's body for DNA identification, loaded back up and left.

Mr Trump said the troops were in the compound for about two hours.

"We lost nobody, think of that," he said.

There was one casualty on the US side, in fact. "Our dog was hurt," he said.

Still, the death of Baghdadi does not mean the end of the ISIS terror group that he led.

French Defence Minister Florence Parly said on her Twitter feed: "Baghdadi: Early retirement for a terrorist, but not for his organisation. We continue the fight against Islamic State, with our partners, and will adapt to new regional circumstances."

Turkish President Recep Tayyip Erdogan's senior aide Fahrettin Altun said in a statement to Reuters: "We remember today Abu Bakr al-Baghdadi's civilian victims and our military heroes, who lost their lives to protect the world from (ISIS) terrorists."