The People's Defence Forces (HPG) said on Wednesday that the murders were a "punishment action" against the two officers, who they claim helped the "Islamic State" (IS) terrorist group in carrying out a suicide attack on Monday, 120 kilometers away in the southeastern city of Suruc.

Both police, Feyyaz Ozsahra and Okan Acarwere, were members of Turkey's anti-terrorism and riot police.

"Although Islamic State has been held responsible for this attack, Turkey's AKP government, by resisting the taking of effective measures to prevent Islamic State and other reactionary forces, bears the real responsibility," the HDP said in a statement.

Turkish newspaper "The Hurriyet" reported that both men had been shot in the head.

Suicide bombing

Thirty-two people died and more than 100 were wounded on Monday, when a suicide bomber targeted a group of young people, mainly university students, close to the Syrian border.

Turkish officials are blaming the attack on IS. The students were holding a press conference on their plans for Syria to rebuild the town of Kobani, after Kurdish forces routed IS militants in January.

Twitter unblocked

Earlier on Wednesday, police officially identified 20-year-old Seyh Abdurrahmen Alagoz as a suspect in the bombing after his identity card was reportedly found at the site.

A ban on Twitter was also lifted later in the afternoon after the Turkish government temporarily blocked access to the site over images of Monday's bombing circulating online.

Wednesday wasn't the first time bans have been implemented on Turkey's social media platforms. The government previously blocked access to YouTube and Twitter during local elections in March 2014 because a secret audio recording of politicians had gone viral. In another instance last April, YouTube, Twitter and Facebook were blocked until they removed photos of a prosecutor who was killed by militants.

ksb/bw (Reuters, AFP, dpa)