ISTANBUL — Suspected Kurdish militants ambushed a Turkish military bus in western Turkey on Thursday in an attack which police said killed one soldier and wounded at least 11 people, adding to a recent upsurge in separatist violence. If confirmed as a Kurdistan Workers Party (PKK) attack, the ambush in the Aegean province of Izmir would represent a widening of the conflict with the PKK beyond its regular field of operation in the mainly Kurdish southeast of Turkey. The violence is a headache for Prime Minister Tayyip Erdogan as he seeks to limit the impact on Turkey of the conflict in Syria, where the PKK is exerting growing authority in some areas and receiving arms from Syrian forces, according to Ankara. “This is unfortunately another example of the steps taken in widening terrorism,” Erdogan told reporters in his first comments on the attack. PKK rebels detonated explosives on the road before firing on the bus at 8 A.M. (0500 GMT) near Foca, a small resort town on the Aegean coast where there is a naval base, Dogan news agency said. The soldiers in the bus returned fire, it said. Television images showed the bus with its windows blown out and glass strewn across the road, and investigators in white overalls searching the scene. Wounded soldiers were taken to a nearby hospital, a police spokeswoman said. It was unclear if the 11 wounded people included any civilians. — Reuters