iraq-turkey- (update 1)-0821-08

* Fourth set of strikes by Turkish warplanes * First report of civilian deaths since strikes began (Adds details, background) ARBIL, Iraq, Aug 21 (Reuters) - Seven Iraqis were killed in an air strike by a Turkish warplane in Iraq's semi-autonomous northern Kurdish zone on Sunday, the first civilian casualties since the strikes began, a local mayor and eyewitnesses said. The strike hit a car in which the civilians were travelling, Hassan Abdulla, mayor of the town of Qalat Dizah, located northeast of the city of Sulaimaniya, told Reuters. "Today there was a rocket from a Turkish plane that hit a civilian vehicle, a pickup, carrying seven civilians. The seven were killed," Abdulla said. "The rocket has badly damaged the car... We could not recognise the bodies, their ages, their identities or even their sex." A Reuters witness said he saw six Turkish warplanes take off from a base in southeastern Turkey on Sunday morning but it was not immediately clear where the planes were headed. Turkish warplanes have been targeting Kurdistan Workers Party (PKK) rebels from Wednesday following increased attacks by the guerrilla forces in southeastern Turkey. The Turkish air strikes are the first against rebels in the mountains of northern Iraq in more than a year and mark a sudden escalation of the 27-year-old conflict after the collapse of efforts to negotiate a settlement. The Turkish General Staff has issued statements on its website confirming three consecutive nights of air strikes on northern Iraq starting on Wednesday night. The last statement appeared on Saturday morning. There did not appear to have been any air strikes on Saturday night. (Reporting by Shamal Aqrawi in Arbil, Seyhmus Cakan in Diyarbakir and Jonathan Burch in Ankara; Writing by Serena Chaudhry; Editing by Sonya Hepinstall)