An image grab taken from a video released on July 5, 2014 by Al-Furqan Media shows alleged Islamic State of Iraq and the Levant (ISIL) leader Abu Bakr al-Baghdadi preaching during Friday prayer at a mosque in Mosul.

Abu Bakr al-Baghdadi, leader of the terrorist group ISIS, is believed to be dead after U.S. forces carried out an operation in Syria, NBC News reported, citing two American officials.

The operation was carried out around midnight in Syria. The U.S. was conducting forensic tests to confirm that Baghdadi was among the dead, according to NBC News, but officials believe he was killed.

The mission came after the U.S. received actionable intelligence regarding Baghdadi in recent days. Various media outlets had previously reported that officials believe Baghdadi was killed.

The news came hours after the White House said late Saturday night that President Donald Trump would be making a "major statement" at 9 a.m. ET Sunday. It wasn't immediately clear what the president would discuss.

The White House statement came more than an hour after Trump tweeted that "Something very big has just happened!" without disclosing further details.

The apparent attack on Baghdadi came days after Trump announced that Turkey agreed to a cease-fire against Kurdish forces in northern Syria. Trump's decision to withdraw troops from the area had triggered concerns that the U.S. was not only abandoning a key ally in its fight against ISIS, but also potentially creating room for an ISIS revival.

Baghdadi, who was born in Iraq, became a key figure in the al Qaida in Iraq terror group in the years following the U.S. invasion of the country. Eventually, that group gave way to Islamic State in Iraq, and Baghdadi rose through its ranks. He would form his own group, the brutal Islamic State of Iraq and Syria, which took over prominent parts of Iraq, including the city Mosul.

U.S.-led forces in turn routed ISIS, forcing it to give up much of the territory it had seized. Baghdadi has been on the run, and has often been rumored to have been killed or gravely hurt.