Arbil, Iraq - Turkish warplanes launched intensive bombing raids on Kurdish rebel targets in northern Iraq overnight but there were no reports of any casualties, a rebel spokesman said on Friday.

The air strikes began at 11.30 p.m. and lasted for three hours, targeting bases belonging to the separatist Kurdistan Workers Party (PKK) and the Party of Free Life of Kurdistan (PJAK), an off-shoot of the PKK fighting against Iran.

"There has been heavy bombing and many Turkish planes were involved. So far, we have no word of any casualties," PKK spokesman Ahmed Danees told Reuters by telephone.

The PKK uses northern Iraq as a base to stage attacks on Turkish territory. Turkey blames the PKK, which is fighting for an ethnic homeland in southeastern Turkey, for the deaths of more than 40,000 people.

Turkish state news agency Anatolian had earlier reported that air strikes began just before midnight and continued into Friday.

Military sources told Reuters that at least 30 planes were involved in the raids, which they said targeted senior PKK members in Iraq's remote Qandil mountains.

Turkish forces have stepped up strikes in the past week against PKK bases in northern Iraq and have launched operations against the rebels inside Turkey. Turkish troops conducted a large-scale incursion across the border in February.

The United States and the European Union consider the PKK a terrorist organization.

(Reporting by Shamal Aqrawi in Arbil, Sherko Raouf in Sulaimaniya and Selcuk Gokoluk in Ankara, writing by Ross Colvin; editing by Keith Weir)