U.S. President Donald Trump confirmed on Sunday that Abu Bakr al-Baghdadi, ISIL's elusive leader, died during an overnight raid carried out by the U.S. military in northwest Syria.

"Last night the United States brought the world's number one terrorist leader to justice. Abu Bakr al-Baghdadi is dead," Trump said.

Trump made the announcement in a televised address from the White House.

The United States has been searching for al-Baghdadi for many years, Trump said. "Capturing or killing Baghdadi has been the top national security priority of my administration."

Trump told reporters al-Baghdadi was under surveillance for a couple of weeks and that two to three planned missions were scrapped before the successful one was launched.

The U.S. president said he watched the operation from the Situation Room.

He said it was a "very dangerous mission." The operation used eight helicopters. And when the special forces entered al-Baghdadi's compound, they were met with local gunfire, he said.

The raid also resulted in the deaths of a large number of al-Baghdadi's fighters and companions, Trump said.

"No (U.S.) personnel were lost in the operation while a large number of Baghdadi's fighters and companions were killed with him," he said.

Al-Baghdadi detonated a suicide vest, killing himself and three of his children after U.S. special forces operators trapped him in a dead-end tunnel in Syria.

Trump said al-Baghdadi died after running into a dead-end tunnel in Idlib province, "whimpering, crying and screaming all the way."

"He died like a dog, he died like a coward," Trump said of the ISIL leader. "The thug who tried so hard to intimidate others spent his last moments in utter fear, panic and dread, terrified of the American forces coming down on him."

Trump said 15 minutes after the death they did on-site DNA test of al-Baghdadi to further identify his body.

Thanks to Russia, Turkey, Syria and Iraq

In his announcement, Trump thanked Russia, Turkey, Syria, Iraq and Syrian Kurds for helping in the mission. He said the Kurdish forces gave the U.S. helpful information and the U.S. flew over certain Turkish and Russian airspace during the mission as those two countries were informed of the operation beforehand.

Washington is a leaking machine

Trump said he didn't notify all members of Congress about the raid.

"We notified some," the President said, "others are being notified now as I speak."

"Washington leaks like I've never seen before," he continued. "There's no country in the world that leaks like we do. Washington is a leaking machine."

Kurds expect ISIL revenge attacks

Syria's Kurdish forces said they expected revenge attacks by the ISIL group following al-Baghdadi's death.

"Sleeper cells will seek revenge for Baghdadi's death," Mazloum Abdi, the top commander of the Syrian Democratic Forces, the de facto army of the Kurdish administration that holds thousands of ISIL fighters in custody, told AFP.

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