BAGHDAD, July 6 (Xinhua) -- Islamic State (IS) militants executed seven people in Iraq's eastern province of Diyala after kidnapping them, a provincial police source said on Friday.

The incident took place late on Thursday night when IS militants set up a fake checkpoint on the main road between Baghdad and the provincial capital Baquba, some 65 km northeast of Baghdad, and kidnapped seven passengers from a minibus, Major Alaa al-Saadi told Xinhua.

Hours later, the bodies of the kidnapped people were found at a nearby orchard riddled with bullets, Saadi said.

Iraqi security forces rushed to the scene and conducted a search operation looking for the attackers, Saadi added.

The incident came despite a major offensive launched two days ago by the security forces, backed by Iraqi warplanes and helicopter gunships, to hunt down the extremist militants in the rugged area in the provinces of Diyala and Salahudin.

On June 30, Iraqi Prime Minister Haider al-Abadi, also the commander-in-chief of Iraqi forces, pledged to hunt down IS militants across Iraq after recent attacks and abductions carried out by the terrorist group.

"We will chase the remaining cells of terrorism in their hideouts; we will kill them, and we will chase them everywhere, in the mountains and the desert," Abadi said.

The latest deterioration in security put the Iraqi security forces under strong criticism for failing to stop the repeated attacks by IS militants on security forces and civilians, as well as the kidnapping of dozens of people at fake checkpoints on a main road between Baghdad and Kirkuk.

On Dec. 9, 2017, Abadi officially declared full liberation of Iraq from the IS. However, small groups of IS militants have since regrouped in rugged areas, carrying out attacks against security forces and civilians from time to time.