The operations in the Avasin-Basyan region, five kilometres (three miles) from the border, were described as "hot pursuits" of Kurdistan Workers' Party (PKK) militants following a rebel attack on a Turkish military outpost Friday.

Special teams involved in the operations were backed by air cover, with Turkish warplanes bombing the area, the sources said.

Turkish forces have carried out similiar "hot pursuit" operations, or brief small-scope forays, in northern Iraq in the past.

The PKK attack on the Aktutun military outpost, which resulted in the killing of six soldiers and 19 militants, prompted a Turkish air raid on PKK positions in Avasin-Basyan late Saturday.

The army said an unspecified number of rebels -- part of a group which had retreated there after the attack -- had been killed and several facilities, including the PKK's media and propaganda centre, destroyed.

Turkey has stepped up military action against the PKK since December, carrying out air strikes plus a week-long ground incursion in February into northern Iraq, where it says more than 2,000 PKK rebels have taken refuge.

The United States has backed its NATO ally by providing intelligence.

The Turkish government has a one-year parliamentary authorisation for cross-border military action against the PKK, which expires in October.

Listed as a terrorist group by Turkey and much of the international community, the PKK has been fighting for self-rule in Turkey's mainly Kurdish southeast since 1984. The conflict has claimed more than 37,000 lives.