Kurdish militants claimed responsibility for the twin bombings that killed 38 and wounded 155, in Istanbul on Sunday, Reuters reported. The Turkish government vowed to take action after the attack. “Sooner or later we will have our vengeance. This blood will not be left on the ground, no matter what the price, what the cost,” Turkey’s Interior Minister Suleyman Soylu said at the funeral of deceased police officers.

The Kurdistan Freedom Hawks, an offshoot of the Kurdistan Workers Party, in a statement on its website, claimed responsibility for the two blasts that took place near Istanbul’s football stadium on Saturday night. The first blast was right outside the stadium, while the second was carried out by a suicide bomber in an adjacent park.

The TAK in its latest statement said the bombings were in response to the ongoing violence in south-eastern Turkey and for the imprisonment of PKK leader Abdullah Ocalan, reported BBC. The militant group was behind other attacks this year, including the Ankara bombings in February 2016 which killed at least 30 people.

Istanbul Police seem to have been the primary target of Saturday’s attacks. Of the 38 people who died, 30 were policemen. Thirteen people have been detained in connection with the attacks, Reuters reported.

The explosions came hours after a parliamentary bill was submitted by Turkey’s ruling party which would expand the tenure and powers of Erdogan, AFP said.