US President Donald Trump revealed in a press conference Sunday that US forces had taken with them "substantial parts" of ISIS leader Abu bakr al-Baghdadi's body after he was killed in a US forces raid.

Trump revealed that "lab technicians" were present at the raid, and some tests were conducted "on site" to establish al-Baghdadi's identity.

Other tests are believed to have been conducted on the remains US forces took with them.

Al-Baghdadi killed himself by detonating a suicide belt while being pursued by US forces in an underground tunnel network in northern Syria.

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US President Donald Trump didn't hold back from revealing in a press conference Sunday the gruesome details of the US special forces raid in northern Syria that left ISIS leader Abu Bakr al-Baghdadi dead.

When a reporter asked whether DNA tests had been conducted to establish al-Baghdadi's identity after he detonated a suicide belt with US forces in pursuit, the president replied that tests had been conducted "on site," and US forces had also taken parts of the terrorist leader's body back with them.

"As I said, they brought body parts back with them, etc., etc. There wasn't much left. The — the vest blew up, but there are still substantial pieces that they brought back," Trump said.

The president didn't disclose further details of the processes used to identify al-Baghdadi, but Fox News national security correspondent Jennifer Griffin reported that the terrorist leader's head survived the explosion intact, allowing US forces to identify him partly using facial recognition technology.

Experts told The New York Times that new technology the US military and intelligence agencies have invested in can conduct DNA tests in as little as 90 minutes.

Further samples and body parts were used to conduct more tests when US forces returned to their base after completing the raid, said a Pentagon official.

Osama bin Laden was buried at sea to prevent a burial site from becoming a shrine — and al-Baghdadi got a similar treatment

The US treatment of al-Baghdadi's remains in some ways mirrors the treatment of al-Qaeda leader Osama bin Laden's remains in 2011, after he was assassinated by US Navy SEALS in a compound in Abbottobad, Pakistan.

In both cases, the remains were given a burial at sea in compliance with Islamic custom.

Three US officials told Reuters Monday that the ritual was performed at sea, but did not disclose exactly where, or how long it lasted. Two of the officials said the remains were disposed at sea from an aircraft.

The US military disposed of Baghdadi's remains "appropriately, in accordance with our (standard operating procedures) and in accordance with the law of armed conflict," U.S. Army General Mark Milley, the chairman of the Joint Chiefs of Staff, told a Pentagon news briefing on Monday.

However there were contrasts, as bin Laden's body survived intact from his death by gunfire from US forces and was transported back with US forces for further tests to conclusively establish his identity.

Even as recently as 2011, DNA tests had to be conducted in a lab. NSA files that Edward Snowden leaked to the Washington Post revealed that the DNA tests to confirm bin Laden's identify were done in a lab in Afghanistan eight hours after the raid.

The Obama administration was conscious that if the final burial site of bin Laden were revealed, it could quickly become a site of pilgrimage for Islamist radicals. So the body was transported to the USS Carl Vinson, where traditional procedures for Islamic burial were observed, and the body was tipped into the Arabian Sea.

"A military officer read prepared religious remarks, which were translated into Arabic by a native speaker," a US defense official said at the time.

Given the nature of al-Baghdadi's demise, it is unlikely the same rituals could have been observed. Bin Laden's body was washed and draped in white sheet before being put in the sea, according to reports.

Business Insider's David Choi reported that US forces destroyed the building where al-Baghdadi died to prevent it from becoming a shrine.

Editor's note: This post was updated on October 29 to make clear that al-Baghdadi's remains were ultimately buried at sea.