Turkey has launched a military operation against Kurdish rebels in northern Iraq, hours after the militants killed 24 soldiers and wounded 18 in attacks in southeastern Turkey near the Iraqi border. Earlier reports put the number of Turkish soldiers killed at 26.

The operation involves Turkish air force bombers and helicopters ferrying troops. Turkish Prime Minister Recep Tayyip Erdogan described the action as “hot pursuit” within the limits of international law, following the deadliest such Kurdish attack in years.

Turkish authorities say rebels from the Kurdistan Workers Party opened fire on military outposts in Cukurca and Yuksekova in Turkey's Hakkari province Wednesday. Turkish President Abdullah Gul told reporters that “vengeance for these attacks will be great.”

The PKK has escalated attacks against Turkish targets in recent weeks. Turkish forces have responded by increasing the number of airstrikes against suspected rebel bases in northern Iraq. In August, Turkey's military said it killed as many as 160 Kurdish rebels in air and artillery strikes across the border.

Kurdish rebels have waged a campaign for autonomy in Turkey's largely Kurdish southeast since 1984. The conflict has killed more than 40,000 people.

The PKK is considered a terrorist group by Turkey, the United States and European Union.