An armed group attacked a border security station at Marivan in Western Iran, killing four people and wounding several others.

It happened at 2AM Saturday at a Kurdistan border crossing post. Mehr News Agency says it was four security forces members who were killed. They were buried today, according to IRNA.

While no organization has claimed responsibility for the attack, Ali Abdollahi, Iran’s deputy interior minister, told Fars News Agency that the Kurdish group Pejak may be involved. “This terrorist operation is different from the two recent terrorist attacks in the city of Sanandaj,” said Abollahi. “However, Pejak has not claimed responsibility for this attack yet.”

The previous attacks occurred on March 25 in Sanandaj, where two Kurdistan security force personnel were killed, and on March 29, when a security vehicle was targeted but no deaths or injuries resulted.

Another attack last month left four environmental guards dead in Kurdistan province, but there have been no clear announcements regarding the motives behind it.

Pejak, or the Kurdistan Free Life Organization, is an anti-Islamic Republic group whose stated mission is to support Iranian-Kurdish rights in the framework of a democratic regime. The Islamic Republic considers Pejak a terrorist group.

In recent years there have been several armed attacks in the Iran-Iraq border region, which have killed several government officers.

In recent months, four people were arrested in Kurdistan and charged with involvement in attacks on security forces.