"A large group of terrorists was neutralised" during the operation on Thursday night which also involved the use of artillery, army general Metin Gurak told a press conference.

The raid came after Turkey's Prime Minister Recep Tayyip Erdogan chaired a meeting of security chiefs to discuss fresh measures against Kurdistan Workers' Party (PKK) rebels after they carried out two deadly attacks in a week.

Gurak said the rebels were "preparing to commit attacks in Turkey," but did not give out any toll for PKK losses from the raid.

The action follows emergency talks involving Turkey's civilian and military leadership in the wake of two attacks on security forces claimed 22 lives in a week.

Erdogan's government is under pressure for tougher action against the PKK after 17 soldiers were killed last Friday when militants crossing from camps in neighbouring Iraq assaulted a border outpost, backed by heavy weapons fire from the other side of the frontier.

It was followed Wednesday by an attack on a police bus in Diyarbakir, the main city of the Kurdish-majority southeast, which claimed five lives.

The bus came under machine-gun fire just as parliament in Ankara extended by one year the government's mandate to order cross-border military operations in northern Iraq against the PKK, which has long enjoyed safe haven in the region.

According to army figures, 25 rebels had died in the military reprisals prior to the fresh raid.