WASHINGTON • The United States has given the remains of Islamic State in Iraq and Syria (ISIS) leader Abu Bakr al-Baghdadi a burial at sea and afforded him religious rites according to Islamic custom, three officials told Reuters.

The US 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.

US Army General Mark Milley, chairman of the Joint Chiefs of Staff, told a Pentagon news briefing on Monday that 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".

Given the gruesome nature of Baghdadi's death, it was unlikely the US military followed as complete a process as it did after Navy Seals killed Al-Qaeda founder Osama bin Laden in a 2011 raid in Pakistan.

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

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