WASHINGTON (Reuters) - The United States has given the remains of Islamic State leader Abu Bakr al-Baghdadi a burial at sea and afforded him religious rites according to Islamic custom after he was killed in a U.S. commando raid in Syria on Saturday, three officials told Reuters.

Baghdadi here, an Iraqi jihadist who rose from obscurity to declare himself "caliph" of all Muslims as the leader of Islamic State, died by detonating a suicide vest after fleeing into a dead-end tunnel as elite U.S. special forces closed in at the weekend, according to the U.S. government.

The U.S. officials, who spoke on condition of anonymity, did not disclose where the ritual was performed or how long it lasted. Two officials said they believed his remains were delivered to the sea from an aircraft.

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

Given the gruesome nature of Baghdadi’s death, it was unlikely the U.S. military followed as complete a process as it did after Navy SEALs killed al Qaeda founder Osama bin Laden in a 2011 raid into Pakistan.

In the case of bin Laden, his body was transported to the aircraft carrier USS Carl Vinson. It was washed before being covered in a white sheet, and religious remarks translated into Arabic were read over bin Laden’s corpse.

Baghdadi’s remains were transported to a secure facility to confirm his identity with forensic DNA testing, Milley said.