Updated

U.S. warplanes carried out airstrikes and dropped humanitarian aid Saturday to Shia Turkmen who have been trapped and besieged by Islamic State militants for two months in the town of Amirli, a U.S. senior defense official confirmed to Fox News.

Aircraft from Australia, France and Britain joined the U.S. in delivering the aid to the farming community about 105 miles north of Baghdad, Pentagon press secretary Rear Adm. John Kirby said in a statement. The aid came at the request of the Iraqi government, he said.

“These military operations were conducted under authorization from the Commander-in-Chief to facilitate the delivery of humanitarian assistance and to prevent an ISIL attack on the civilians of Amirli,” Kirby said. “The operations will be limited in their scope and duration as necessary to address this emerging humanitarian crisis and protect the civilians trapped in Amirli.”

A statement from U.S. Central Command (Centcom) said the airstrikes and aid drop took place at approximately 8:30 p.m. Eastern Time Saturday. The aid drop consisted of 109 bundles containing approximately 10,500 gallons of fresh water and approximately 7,000 meals ready to eat (MRE). Centcom said the airstrikes destroyed three ISIS Humvees, one ISIS armed vehicle, one ISIS checkpoint and one ISIS tank. The attacks bring the total number of airstrikes in Iraq to 118 since August 8.

Instead of fleeing in the face of the Islamic State drive across northern Iraq, the Shiite Turkmens have stayed and fortified their town of 15,000 with trenches and armed positions.

Iraqi troops began a coordinated push to retake the town from ISIS on Saturday. Its water and electricity have been cut off since June and surrounded by militants since mid-July.

Some residents have said that the Iraqi military's efforts to fly in food, water and other aid have not been enough amid oppressive heat, lack of electrical power -- the town's power station was destroyed weeks ago -- and shelling from the militants.

The U.S. had been watching the area closely in case a slaughter of the Turkmen appeared imminent and air support was needed, said Michael Knights, who studies Iraq and the Persian Gulf as a fellow of The Washington Institute. U.S. airstrikes will hasten the success of the relief effort on the ground, he said.

About half of the town's population is age 15 and under while many others are elderly, sick or wounded, Knights said.

"They are remarkably vulnerable, and ISIS is determined to kill as many of these people as possible," Knights said, referring to an acronym for the Islamic State group. "As the Nazis felt about the Jews, so ISIS feels about the Shia Muslims."

The Turkmen are Iraq's third largest ethnic group after Arabs and Kurds. They make up about 4 percent of Iraq's population. Iraqi forces were airlifted into the area on Saturday

U.S. airstrikes in Iraq, which began earlier this month, have targeted Islamic State militants attacking Yazidi Iraqis on Mount Sinjar and the militant forces operating in the vicinity of Ibril and Mosul Dam. The beleaguered Yazidis received several humanitarian drops of tons of food and water as well as military support aimed at protecting them.

Earlier Saturday, U.S. Central Command said five more airstrikes carried out by fighter aircraft and unmanned drones had taken place against Islamic State militants near Mosul Dam.

The Associated Press and Fox News’ Jennifer Griffin contributed to this report.