LATEST DEVELOPMENTS

• The United Nations announced its highest level of emergency for the humanitarian crisis in Iraq, where hundreds of thousands have been driven from their homes by the advance of Islamic militants across the north of the country.

• Breaking ranks with other European countries, France announced that it would send arms to the Kurdish authorities fighting the militants in northern Iraq.

• Embattled Prime Minister Nouri al-Maliki said he would press ahead in the Iraqi courts with his increasingly unlikely bid to retain power and would not turn to the army.

• Iraqi troops imposed heightened security in Baghdad. Attacks in and near the capital killed at least 29 people and wounded scores more, police said.

— From news services

Defense officials said late Wednesday that U.S. airstrikes and Kurdish fighters had broken the Islamic State’s siege on Iraq’s Mount Sinjar, allowing thousands of minority Yazidis trapped there to escape.

An initial report from about a dozen U.S. Marines and Special Operations forces who had spent the day on the mountain indicated that “the situation is much more manageable,” a senior defense official said in an interview.

“A rescue effort now is far less likely now,” Defense Secretary Chuck Hagel told reporters at Andrews Air Force Base outside Washington.

Defense officials said several thousand Yazidis remained on the mountain far fewer than the 30,000 earlier reported to stillbe in danger there.

The announcement capped a daylong buildup that began when Obama administration officials suggested a rescue mission was in the offing after several days of U.S. airdrops of food and supplies to the stranded Yaidis. The group, which combined Islamic, Christian and Zoroastrian beliefs and is derided as heretics by the Islamic State militants, had fled their home territory as the insurgents approached.

“We would be the first to acknowledge that’s not a permanent solution, just dropping food and water in perpetuity from the air,” Ben Rhodes, Obama’s deputy national security adviser, told reporters in Washington.

Among options Rhodes said were under consideration was establishing protected corridors that would allow the Yazidis to escape the mountain without facing Islamic State forces dedicated to their extermination. Rhodes said the possibility of airlifting some of the Yazidis was also being considered.

“You look at corridors, you look at airlifts, you look at different ways to move people who are in a very dangerous place on that mountain to a safer position, and that’s exactly what our team is doing now on the ground now in Iraq,” Rhodes said.

The United States sent four V22 Osprey tilt-rotor aircraft to Irbil, commonly used by the Marine Corps and special operations troops, and one made a dramatic appearance, firing off anti-missile flares as it descended into the airport there.

But the report from the U.S. military who scouted Mount Sinjar indicated the number of Yazidi stranded there was far fewer than in a Tuesday United Nations estimate.

“The team has assessed that there far fewer Yazidis on Mount Sinjar than previously feared, in part because of the success of the humanitarian air drops, airstrikes on ISIL targets, the efforts of the peshmerga and the ability of thousands of Yazidis to evacuate from the mountain each night over the last several days,” a Pentagon statement said. “The Yazidis who remain are in better condition than previously believed and continue to have access to the food and water we have dropped.”

The statement concluded, “Based on this assessment, the interagency (sic) has determined that an evacuation mission is far less likely.”

It added, “We will continue to provide humanitarian assistance as needed and will protect U.S. personnel and facilities.”

Hagel credited six days of U.S. airstrikes that he said drove back the militants, giving the Yazidis the opportunity to get off the mountain.

Any U.S. military-led rescue mission on Sinjar Mountain could have involved putting American troops on the ground, though the White House insisted their mission would be strictly a humanitarian rescue and would not constitute a return to combat 2 1/2 years after the last U.S. troops withdrew from Iraq.

“We don’t believe that involves U.S. troops re-entering a combat role in Iraq,” Ben Rhodes, Obama’s deputy national security adviser, said before the assessment was delivered. “It involves frankly a very difficult logistical challenge of moving folks who are in danger on that mountain into a safer position.”

The Pentagon sent 129 U.S. troops to Iraq on Tuesday to assess the scope of the humanitarian crisis and the options for getting the Yazidis safely off the mountain. The secret scouting mission to the mountain Wednesday involved a team of fewer than 20 U.S. troops flown in by Black Hawk helicopter, according to a defense official. The team was safely extracted hours later.

Also Wednesday, in the latest of several strikes, a U.S. drone aircraft attacked and destroyed an armed truck operated by Islamic militants near Sinjar, the U.S. Central Command said.