WASHINGTON — The surprising information about the Islamic State leader Abu Bakr al-Baghdadi’s general location — in a village deep inside a part of northwestern Syria controlled by rival Qaeda groups — came following the arrest and interrogation of one of Mr. al-Baghdadi’s wives and a courier this past summer, two American officials said.
Armed with that initial tip, the C.I.A. worked closely with Iraqi and Kurdish intelligence officials in Iraq and Syria to identify Mr. al-Baghdadi’s more precise whereabouts and to put spies in place to monitor his periodic movements, allowing American commandos to stage an assault Saturday in which President Trump said Mr. al-Baghdadi died.
But Mr. Trump’s abrupt decision to withdraw American forces from northern Syria disrupted the meticulous planning and forced Pentagon officials to press ahead with a risky, night raid before their ability to control troops and spies and reconnaissance aircraft disappeared, according to military, intelligence and counterterrorism officials. Mr. al-Baghdadi’s death, they said, occurred largely in spite of Mr. Trump’s actions.
The officials praised the Kurds, who continued to provide information to the C.I.A. on Mr. al-Baghdadi even after Mr. Trump’s decision to withdraw the American troops left the Syrian Kurds to confront a Turkish offensive alone. The Syrian and Iraqi Kurds, one official said, provided more intelligence for the raid than any single country.
The initial planning for the raid began this past summer. The Army’s elite Delta Force commando unit began drawing up and rehearsing plans to conduct a secret mission to kill or capture the ISIS leader, and faced huge hurdles. The location was deep inside territory controlled by Al Qaeda. The skies over that part of the country were controlled by Syria and Russia. The military called off missions at the last minute at least twice.
“It wasn’t until Thursday and then Friday the president chose his option and gave us the green light to proceed as we did yesterday,” Defense Secretary Mark T. Esper said on ABC’s “This Week” on Sunday.
Mr. Esper said he did not know if the United States would have been able to carry out the helicopter raid against Mr. Baghdadi’s compound had American troops been completely withdrawn from Syria, as Mr. Trump had originally planned.
“I’d have to consult with our commanders about that,” Mr. Esper said on CNN’s “State of the Union.”
In addition to Mr. Trump’s account, more than a half-dozen Pentagon, military, intelligence and counterterrorism officials provided this chronology of the raid after the president approved the operation.
Around midnight Sunday morning — 5 p.m. Saturday in Washington — eight American helicopters, primarily CH-47 Chinooks, took off from a military base near Erbil, Iraq.
Flying low and fast to avoid detection, the helicopters quickly crossed the Syrian border and then flew all the way across Syria itself — a dangerous 70-minute flight in which the helicopters took sporadic groundfire — to the Barisha area just north of Idlib city, in western Syria. Just before landing, the helicopters and other warplanes began firing on a compound of buildings, providing cover for commandos with the Delta Force and their military dogs to descend into a landing zone.
Mr. Trump seemed eager to provide details of the raid during a White House news conference on Sunday.
The president said that with the helicopter gunships firing from above, the commandos bypassed the front door, fearing a booby trap, before destroying one of the compound’s walls. That allowed them to rush through and confront a group of ISIS fighters.
The president, along with Mr. Esper, Vice President Mike Pence, and Gen. Mark A. Milley, the chairman of the Joint Chiefs of Staff, watched full-motion video of the raid that was piped into the White House Situation Room from surveillance aircraft orbiting over the battlefield.
The Delta Force commandos, under fire, entered the compound, where they shot and killed a number of people. Mr. Trump said they also removed 11 children from harm’s way,
Mr. al-Baghdadi ran into an underground tunnel, with the American commandos in pursuit. Mr. Trump said that the ISIS leader took three children with him, presumably to use as human shields from the American fire. Fearing, apparently correctly, that Mr. al-Baghdadi was wearing a suicide vest, the commandos dispatched a military dog to subdue Mr. al-Baghdadi, Mr. Trump said.
It was then that the Islamic State leader set off the explosives, wounding the dog and killing the three children, Mr. Trump said.
Mr. Esper described the climax of the two-hour ground raid on “This Week” this way: “He’s in a compound, that’s right, with a few other men and women with him and a large number of children. Our special operators have tactics and techniques and procedures they go through to try and call them out. At the end of the day as the president said, he decided to kill himself and took some small children with him, we believe.”
Mr. Trump was more descriptive. “I got to watch much of it,” he said. Mr. al-Baghdadi, he said, “died after running into a dead-end tunnel, whimpering and crying and screaming all the way.” The president said that Mr. Baghdadi “had dragged three of his young children with him,” and that the Islamic State leader “ignited himself, killing himself and the three children.”
Mr. Esper did not repeat the “whimpering” and “crying” assertion made by Mr. Trump. “I don’t have those details,” he said. “The president probably had the opportunity to talk to the commanders on the ground.”
Altogether, the American troops were on the ground in the compound for around two hours, Mr. Trump said, clearing the buildings of fighters and scooping up information that the president said contained important details on ISIS operations. Mr. Trump said the commandos already had DNA samples from the Islamic State leader, which he said they used to make a quick assessment that they had the right man.
Once all the Americans had piled back into their helicopters and started the return flight to Iraq — using the same route out as they used coming in, Mr. Trump said — American warplanes bombed the compound to ensure it was physically destroyed, Mr. Esper said. Just after 9 p.m. Washington time Saturday — four hours after the helicopters took off — Mr. Trump tweeted, “Something very big has just happened!”