Tom Vanden Brook

USA TODAY

WASHINGTON — U.S. warplanes conducted a fresh round of airstrikes and emergency aid drops at a new site in Iraq to thwart Islamic State militants threatening a town populated by an ethnic minority, the Pentagon announced late Saturday night.

The strikes and humanitarian aid missions were flown near the town of Amirli, home to Turkmen, an ethnic minority. The operation is similar to the one mounted at Mount Sinjar, not far away in northern Iraq, to help save Yazidis, a religious minority that IS had besieged.

"These military operations were conducted under authorization from the commander-in-chief to facilitate the delivery of humanitarian assistance and to prevent an (IS) attack on the civilians of Amirli," Rear Adm. John Kirby, the Pentagon press secretary, said in a statement. "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."

Saturday's strikes and drops widened the U.S. effort to confront the IS, which has seized territory from Syria and across northern Iraq. Its brutal tactics, including the beheading of U.S. journalist James Foley, have heightened the sense of urgency to confront them.

U.S. fighter jets attacked and destroyed three IS Humvees, a tank, an armed vehicle and a checkpoint near Amirli, according to a statement from U.S. Central Command, which oversees military operations in the Middle East. Also, U.S. cargo planes dropped 109 bundles of food and water. Australian, British and French aircraft also flew humanitarian missions.

Since early August, the 118 airstrikes have mostly focused on areas around Mosul dam in northern Iraq. IS fighters had seized the dam and sparked fears that its destruction could inundate Iraq's most populous areas, including Baghdad. There were also concerns that IS, whose string of conquests had been unbroken, might overrun Irbil, the capital of Iraq's Kurdish region.

The airstrikes have allowed Kurdish fighters and Iraqi special forces to retake the dam and push militants back from Mosul. This week, several Western countries have agreed to send arms to the Kurds.

Saturday's effort expands the target list and widens the effort against IS. American spy planes have begun surveillance missions on potential IS targets in neighboring Syria where the militants got their start.

The Pentagon estimates operations in Iraq cost $7.5 million per day.

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