WASHINGTON — Defense officials said late Wednesday that U.S. airstrikes and Kurdish fighters had broken the siege on Mount Sinjar, allowing thousands of the Yazidis trapped there to escape.
An initial report from about a dozen Marines and special operations troops who had spent the past 24 hours on the northern Iraqi mountain said that "the situation is much more manageable," the New York Times reported, citing a senior defense official.
A rescue effort involving U.S. troops is now much more unlikely, the official said.
Defense officials could not say how many Yazidis remained on the mountain, but Defense Secretary Chuck Hagel was expected to make a statement later.
U.S. military advisers landed on Mount Sinjar early Wednesday to begin assessing how to organize an evacuation. The United States had said it would consider using ground troops to assist in the rescue if recommended by the military team.
Hagel said it was "far less likely now" that the United States would undertake a rescue mission because the assessment team reported far fewer refugees than previously thought and those still on the mountain were in relatively good condition.
Several thousand Yazidis remain on the mountain, a senior U.S. official said, but not the tens of thousands who were originally believed to be there. Some of the people who remain on Mount Sinjar indicated to U.S. forces that they considered the mountain to be a place of refuge and a home, and did not want to leave, the Times reported, citing a second U.S. official. Both officials spoke on the condition of anonymity because they were not authorized to speak publicly on the issue.
Rear Adm. John Kirby, the Pentagon press secretary, said in a statement that "the team has assessed that there are far fewer Yazidis on Mount Sinjar than previously feared, in part because of the success of the humanitarian airdrops."
He credited U.S. airstrikes as well as the "efforts of the peshmerga and the ability of thousands of Yazidis to evacuate from the mountain each night over the last several days." Defense officials said the evacuations were done in secret with the help of Kurdish peshmerga fighters.
The latest twist came just hours after Benjamin J. Rhodes, deputy national security adviser, told reporters in Martha's Vineyard, where President Barack Obama is vacation, that the president was likely to receive recommendations about how to mount a rescue operation in the next several days. He said those recommendations could have included the use of U.S. ground troops.
But Rhodes made those comments as the secret team of Marines and special operations forces were already on the ground on Mount Sinjar in the middle of a 24-hour trip to talk to the refugees and peshmerga fighters on the mountain.
For Obama, who has been reluctant to commit additional U.S. ground troops to Iraq, the report was welcome news. Obama had maintained — even when announcing that he had authorized airstrikes to help break the siege — that he would not be sending U.S. combat troops to the country they left in 2011.
But as reports from Mount Sinjar became increasingly dire, amid video images of the suffering Yazidis, the president found himself weighing a host of options for a rescue operation.
The leading option before the siege was broken was to rescue the Yazidis with a combination of ground troops — mostly Kurdish peshmerga but with help from U.S. special operations forces and Marines. The United States was also discussing using airlifts that could have included American V-22 Ospreys, which are hybrid aircraft that can take off and land like helicopters but which, once in the air, have the speed and range of propeller planes.
But both of those options came with a host of complications, including increased risks that Islamic State of Iraq and Syria militants could attack the Ospreys, which could result in casualties to both American pilots and evacuees. Some Iraqi and Kurdish helicopters had managed to carry a few dozen refugees to safety, but officials said the aircraft had frequently been fired upon by ISIS fighters.
A corridor of escape on the ground — which would have been guarded primarily by Kurdish peshmerga fighters and backed by some U.S. troops — brought its own set of problems, Defense Department officials said. The most direct route off the mountain is south, with the goal of reaching territory still held by the Iraqi government in Baghdad. But that route would have taken the rescue forces and Yazidis through areas controlled by ISIS, increasing the potential for combat and casualties.
The speed with which the Obama administration announced that the siege had been broken could cause some consternation overseas, given the increasingly dire descriptions from aid agencies about the crisis on Mount Sinjar. The United Nations on Wednesday announced its highest level of emergency for the humanitarian crisis in Iraq.