Turkey's parliament has voted to extend the military's authority to conduct operations against Kurdish rebels in northern Iraq.

Turkish lawmakers passed a motion by a wide margin extending the military's mandate to carry out cross-border missions for one year.

The vote comes less than one week after fighters from the Kurdistan Workers Party, or PKK, killed 17 Turkish soldiers during a raid on a military outpost near the Iraqi border.  Turkey's military pounded back since the attack.  It says it has killed more than 20 militants in air raids against rebel hideouts in southeastern Turkey and northern Iraq.

At least four police officers and one other person were killed and at least 15 others wounded Wednesday, when a police vehicle was attacked near Diyarbakir, in mainly Kurdish southeastern Turkey.  There was no immediate claim of responsibility.  

Before parliament convened for the vote, Prime Minister Tayyip Erdogan indicated that the army may launch new ground operations inside Iraq.  He also said he would consider opposition calls to set up a military buffer zone along the Iraqi border.

Turkish military officials have accused Iraq's Kurdish leaders of tolerating Kurdish rebels and of refusing to cooperate with Turkish forces.

Iraq's Kurdish regional government and presidency deny they support the PKK.

Turkey has been battling PKK rebels since 1984, when the group launched an armed campaign for an ethnic homeland in southeast Turkey.

The PKK is classified as a terrorist organization by Turkey, the United States and the European Union. 

Some information for this report was provided by AP.