Turkish warplanes bombed Kurdish rebel hide-outs in northern Iraq on Tuesday, as Turkey's deputy military commander visited Baghdad to discuss cooperation in fighting the rebels, the military said.

It was the fourth aerial attack on rebel positions in northern Iraq since the military began a bombing campaign Dec. 16. Prime Minister Recep Tayyip Erdogan vowed on Monday to "finish" the rebels soon.

In Tuesday's attack, the jets "effectively struck" at Kurdish rebel targets in the areas of the Zap-Sivi, Avasin-Basyan and Hakurk regions, the military said on its Web site.

Zirar Mohammed, a top administrative official in the border town of Sedakan in Erbil, and Col. Hussein Tamir of the border forces in Dahouk said that the Turkish bombardment started at around 11:30 a.m. (0930 GMT).

The military said the bombardment had ended and all aircraft returned safely.

Private NTV television, citing Iraqi Kurdish officials, said about 10 jets participated in the raids.

The military said the air assault targeted only confirmed rebel positions and that efforts were made to avoid harming the civilian population.

The rebel Kurdistan Workers' Party, or PKK, has battled for autonomy in southeastern Turkey for more than two decades — a campaign that has resulted in tens of thousands of deaths. It uses strongholds in northern Iraq for cross-border strikes into Turkey.

Making a surprise visit to Baghdad, the Turkish military's second-in-command, Gen. Ergin Saygun, met with Iraqi Lt. Gen. Nasier Abadi, deputy chief of staff for the Iraqi army, as well as with Gen. David Petraeus, the top U.S. commander in Iraq, the military said in a separate statement.

They discussed fighting Kurdish rebels and possible military cooperation, the army said.

It was a first visit to Iraq by a top Turkish commander since the U.S.-led invasion in 2003.

In October, the Turkish parliament authorized the military to strike at the rebels across the border.

"We would hope to finish them soon but we cannot say when," Erdogan said during a visit to Madrid on Monday. "We have information that tells us we may have to continue with these operations."

Erdogan said his government would seek parliament's authorization to extend the operations, if necessary.

Turkey launched the bombing campaign Dec. 16 and claimed to have killed as many as 175 rebels in that first raid. Three other air raids and a brief ground incursion followed.

The United States — which with Turkey and the European Union considers the PKK a terrorist organization — has cautioned Ankara against a large incursion, fearing it could disrupt one of Iraq's most stable regions.

In an apparent retaliation for Turkish attacks, suspected Kurdish militants blew up a car bomb in the southeastern city of Diyarbakir Jan. 3, killing six civilians and injuring 67 others — including dozens of army officers.