(ABC)

President Donald Trump announced the death of Abu Bakr al-Baghdadi, the leader of the Islamic State, on Sunday.

“A brutal killer, one who has caused so much hardship and death, has violently been eliminated,” Trump said in an address to the nation from the White House. “He will never again harm another innocent man, woman or child. He died like a dog. He died like a coward. The world is now a much safer place.”

Trump said he was able to watch most of the operation in the situation room as it happened.

“Al-Baghdadi was vicious and violent and he died in a vicious and violent way. As a coward running and crying,” Trump said. “This raid was impeccable and could only have taken place with the acknowledgment and help of certain other nations and people. I want to thank the nations of Russia, Turkey, Syria, and Iraq and I also want to thank the Syrian Kurds for certain support they were able to give us.”

Defense Secretary Mark Esper appeared on ABC’s “This Week” following the president’s remarks and described more details of the military operation, saying the starts started lining up a couple of weeks ago. He said troops rehearsed the mission and then on Thursday and Friday chose the option they would proceed with on Saturday.

Trump said he and his national security team gathered in the White House situation room shortly after 5 p.m. to watch the mission. A short time later, eight helicopters carrying the special operations team took off from an undisclosed location in a nearby country for a 1 hour, 10 minute flight to al-Baghdadi’s compound. The president said that flight was a dangerous part of the mission given they would be flying over Russian- and extremist-held territory.

Once the helicopters landed near the compound, the troops made their way to the building and blew holes into the side of the building to avoid the main door. There was a firefight and an unknown number of fighters were killed.

Al-Baghdadi grabbed three of his children and ran into an escape tunnel, where he was eventually cornered by a U.S. military dog, Trump said. The president described al-Baghdadi as, “whimpering, crying and screaming the whole time.”

There were no American troops wounded in the operation, but a military dog was hurt when al-Baghdadi’s vest was detonated and the tunnel collapsed, Trump said.

The president said al-Baghdadi’s body was significantly damaged by the blast, but there were enough remains to positively identify him through a visual identification and an on-site DNA test.

Rumors had swirled since at least 2014 that al-Baghdadi had been wounded, or possibly even killed, but he’d often quash those himself by releasing audio recordings.

U.S. special forces nearly killed him in August 2017, destroying a compound south of Ragga in which he was believed to have been during a massive bombardment. The following month, he released an audio recording to prove he’d survived.

The ISIS leader was last seen alive in a video in April.

There had been a $25 million U.S. bounty on the head of al-Baghdadi, who, in his only previous video, recorded in a Mosul mosque in 2014, called himself “Caliph,” or leader of all Muslims.

The president said American forces were in the compound for about two hours after the mission and collected sensitive information.

Esper added that, “we destroyed the target site to ensure it was physically destroyed.”

After the troops were safely returned from the compound, the president tweeted, “Something very big has just happened!”

Asked by “This Week” Co-Anchor Martha Raddatz on Sunday about the possible uptick in violence following al-Baghdadi’s death, Esper said, “When you take out a leader like that, it’s going to have, I think, a major impact on the organization, but we’ll see over time.”

“I am grateful to our President and brave troops for finding ISIS leader Al-Bagdadi,” Diane Foley of the James W. Foley Legacy Foundation said in a statement. “I hope this will hinder the resurgence of terror groups and pray that captured ISIS fighters will be brought to trial and held accountable. I remain concerned about the dozen Americans held hostage in Syria, including Austin Tice and Majd Kamalmaz.”

An image made from video posted on a militant website on April 29, 2019, purported showed the leader of the Islamic State group being interviewed by his group’s Al-Furqan media outlet. Al-Baghdadi acknowledged in his first video since June 2014 that IS lost the war in the eastern Syrian village of Baghouz that was captured last month by the Kurdish-led Syrian Democratic Forces.

Abu Bakr al-Baghdadi

In a statement, Secretary of State Mike Pompeo said al-Baghdadi met the fate he long deserved.

“While there is still work left to do to ensure ISIS’s enduring defeat, Baghdadi’s death follows the path of scores of other ISIS leaders that have been removed from the battlefield and can no longer commit heinous atrocities or spread their vile ideology of hatred to poison and recruit vulnerable minds. His evil acts of beheadings, enslavement of women, rape, torture, and pure brutality follows him to his grave,” Pompeo said in the statement.

Following the president’s remarks and press conference, Sen. Lindsey Graham, R-S.C., told reporters that al-Baghdadi’s death was a “game changer.”

“The best of America confronted the worst kind of mankind, and America won,” he said.

“This is where Trump’s worst critics should say well-done,” Graham added.

During his press conference, Trump said he did not inform Democratic leaders about the mission, but did tell a small group of Republican lawmakers.

ABC News Senior National Correspondent Terry Moran asked Graham if that was appropriate, but Graham said it was not his place to comment on that.

“Last night was a great night for the United States and for the world,” Trump said.