(FILES) This image grab taken from a propaganda video released on July 5, 2014 by al-Furqan Media allegedly shows the leader of the Islamic State (IS) jihadist group, Abu Bakr al-Baghdadi, aka Caliph Ibrahim, adressing Muslim worshippers at a mosque in the militant-held northern Iraqi city of Mosul. 
The Russian army on June 16, 2017 said it hit Islamic State leaders in an airstrike in Syria last month and was seeking to verify whether IS chief Abu Bakr al-Baghdadi had been killed. In a statement, the army said Sukhoi warplanes carried out a 10-minute night-time strike on May 28 at a location near Raqa, where IS leaders had gathered to plan a pullout by militants from the group's stronghold.
 / AFP PHOTO / AL-FURQAN MEDIA / --/AFP/Getty Images
What we know about ISIS leader Abu Bakr al-Baghdadi
04:09 - Source: CNN
Washington CNN  — 

Defense Secretary Mark Esper described the death of ISIS leader Abu Bakr al-Baghdadi as a “devastating blow” to a terrorist organization that has launched horrific attacks across the world.

“This is a devastating blow. This is not just their leader, it’s their founder. He was an inspirational leader in many ways. He formed ISIS in 2014, he led to establishing the physical caliphate throughout the region, so this is a major blow to them,” Esper told Jake Tapper Sunday on CNN’s “State of the Union.”

Esper added that “we’re going to watch carefully next steps. And as a new leader and leaders pop up we’ll go after them as well.”

The secretary told Tapper that President Donald Trump approved the US raid “late last week” after being presented with different options. The objective, Esper said, was capturing him or if necessary, killing him.

“The President approved a raid on the target, Abu Bakr al-Baghdadi, and if we didn’t capture him, of course, we were going to kill him,” Esper said.

“He reviewed them, asked some great questions, chose the option that we thought gave us the highest probability of success and confirmation that the head of ISIS would be there and either captured and killed and then we executed from there,” Esper said.

“The President made a very decisive action and our troops and our interagency partners executed it brilliantly.”

The secretary explained that al-Baghdadi refused to surrender to US forces before detonating a suicide vest and killing himself during a US military raid in northwest Syria on Saturday.

Asked by Tapper if Baghdadi took his own life during the operation, Esper said, “That’s the report we have on the ground from the commander.”

“We tried to call him out and ask him to surrender himself. He refused. He went down into a subterranean area, and in the process of trying to get him out he detonated a suicide vest, we believe, and killed himself,” Esper said.

Baghdadi, the leader of the terror group, was believed to have been in hiding for the last five years. Esper said the Pentagon has confirmation that it was Baghdadi “through a form of visual and also DNA confirmation.”

Esper also said there were two minor US injuries to soldiers in the operation. President Trump had only indicated a US K-9 was injured.

“We had two minor casualties, two minor injuries, to our soldiers,” Esper said. “They’ve already returned to duty.”

CNN’s Ryan Browne and Phil Mattingly contributed to this report.