Turkey said it has airlifted troops for a cross-border ground operation against Turkey’s Kurdish rebels in northern Iraq, the first known airborne-and-land offensive by Ankara inside Iraqi territory.

The airborne offensive into Iraq’s border region of Haftanin, some 15 kilometers from the Turkey-Iraq border, was launched following intense artillery fire into the area.

Turkey regularly carries out air and ground attacks against the outlawed Kurdistan Workers Party, or PKK, which it says maintains bases in northern Iraq. Wednesday’s was the first known airborne and land offensive.

The ministry said Wednesday’s operation follows “increasing harassment and attempts to attack” military outposts or bases in Turkey. It said the Turkish forces would target other “terror” groups in the region, but did not name them.

A military official said the operation began with artillery units targeting some 150 suspected PKK positions and was followed by an aerial attack involving F-16s, drones and attack helicopters.