A U.S. military aircraft flies over the Incirlik Air Base in southern Turkey in late July. (Emrah Gurel/AP)

The United States has begun conducting airstrikes over Syria from a base in southern Turkey, the Pentagon said Wednesday, opening a new front in the Obama administration’s air war against the Islamic State.

Capt. Jeff Davis, a Defense Department spokesman, told reporters at the Pentagon that a U.S. drone had hit an Islamic State target in Syria on Tuesday. He declined to say exactly where the strike took place or whether it was successful.

The beginning of combat flights from Incirlik Air Base is a sign of deepening U.S.-Turkish cooperation against militants in Syria, where the expansion of the Islamic State poses a growing threat to Turkey and the West.

Before this week, Ankara had only permitted the United States to fly surveillance missions from Incirlik, forcing it to rely largely on more distant bases­ and cutting down on the time U.S. aircraft can spend over target areas.

Davis said the Pentagon would place manned fighter jets at Incirlik in the near future. He said the new operations from Turkey would “put coalition aircraft significantly closer on the map to where these potential targets are.”

In particular, the new combat flights will give the United States easier access to a “safe zone” the two countries are planning for northern Syria. The proposal aims to establish an area close to Syria’s border with Turkey that would be cleared of Islamic State fighters.

In comments carried by Syrian state television on Wednesday, Syrian Foreign Minister Walid al-Moualem said his country would support efforts to combat the Islamic State on Syrian soil provided they were coordinated with the government of President Bashar al-Assad, Reuters reported.

The Obama administration maintains that it does not coordinate military efforts with Assad, a leader who the White House says no longer has legitimacy to govern.

Turkey has also allowed the United States to establish a training site there for the Pentagon’s program to build up a new Syrian force to fight the Islamic State. The program has suffered a host of setbacks, most recently the abduction this week of five U.S.-trained fighters by al-Qaeda’s Syrian affiliate.