It is the second such Turkish air strike in one week

Fighter planes attacked positions held by the Kurdistan Workers' Party (PKK) in a 35-minute raid, the army said.

Similar air strikes last Sunday were followed two days later by an incursion into Iraq by Turkish troops.

Iraq's Kurdish regional government condemned those raids, but Turkey says it has a right to defend itself from PKK attacks on its territory.

Operations 'to continue'

In a statement on its website, the Turkish military said: "Turkish Air Force warplanes struck important targets of the PKK/KONGRA-GEL terror group in northern Iraq... between the hours of 14:25-15:00 (1225-1300 GMT).

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The air strikes were followed by shelling from inside the Turkish border, army officials said.

Ten planes were involved in the raid, senior military sources told Reuters news agency.

Officials did not disclose the location of the raids, although Iraqi Kurdish authorities said the target was in a mountainous region north of the town of Dohuk.

The US administration confirmed that it had been informed of the attacks in advance.

No casualties were reported by authorities in northern Iraq.

"The aerial bombardment didn't result in any people killed because the area is almost deserted because of fear of aerial and mortar attacks from the Turkish side," Reuters news agency quoted Jabbar Yawer, an Iraqi Kurdish Peshmerga spokesman as saying.

Turkish military officials pledged to continue operations "no matter how the conditions are", the Associated Press news agency quoted the army statement as saying.

Stability threat

Turkish officials said the PKK "suffered heavy losses in terms of its infrastructure and its human resources," during the military operation earlier this month.

Turkish foreign ministry spokesman Levent Bilman told the BBC the United States "supplied actionable intelligence" for that operation.

The US is opposed to any major cross-border incursion into the only relatively stable region of Iraq but has agreed to share intelligence with Turkey - a vital strategic ally - on the PKK.

The PKK - which is designated a terrorist organisation by Turkey, the US, and the EU - is thought to have about 3,000 rebels based in Iraq.