Turkish Prime Minister Recep Tayyip Erdogan said Thursday that Turkey had launched a cross-border military operation into five regions in northern Iraq in fight against the outlawed Kurdish Workers' Party (PKK).

The Turkish army has sent 22 battalions, about 10,000 soldiers, into five regions including northern Iraq, according to Thursday's reports of Turkish leading newspaper Hurriyet Daily News.

The Air Force also launched an operation Wednesday as fighter jets bombed PKK camps in Qandil, Hinere, Zap and Hakurk in northern Iraq, according to reports.

Clashes between PKK militants and Turkish troops who entered northern Iraq from three different routes were still underway, while reports said that commando units were being dropped into northern Iraq by helicopters.

Turkish army initiated the operation in five separate regions in the north of Iraq and in Turkey following Wednesday's PKK attack which killed 24 soldiers and injured 18 others in the southeastern Turkish province of Hakkari, Turkish Anatolia news agency quoted General Staff as saying on Thursday.

PKK terrorists staged synchronous attacks in eight different zones in Hakkari at around 1 a.m. (2200 GMT Tuesday) on Wednesday, according to a Thursday's announcement issued by Turkish General Staff's website.

In response, Turkey deployed a special team, two Cobra helicopters and two Skorsky helicopters in the region at 1:48 a.m. (2248 GMT Tuesday), and opened fire on terrorist targets, said the statement, adding that Chief of General Staff Gen. Necdet Ozel and commanders of forces had also reached the region.

Four of the injured soldiers, who were in serious condition, had been taken to GATA military hospital in Ankara while other 14 wounded soldiers were under treatment at hospitals in Hakkari and southeastern province of Sirnak, according to the Anatolia report.

VietNamNet/Xinhuanet