TEHRAN - Iranian security forces have killed three people in the western province of Kurdistan who were behind an attack on a group of environmental workers, the official IRNA news agency reported on Thursday.
IRNA said the three had killed four environmental workers near the city of Sanandaj last Friday.
"Three terrorists ... were killed in clashes with security forces on Wednesday night. Another terrorist was also injured and later arrested," it said.
Security forces in the west of Iran often clash with guerrillas from PJAK, an offshoot of the Kurdistan Workers' Party (PKK), which took up arms in 1984 for an autonomous ethnic state in southeast Turkey and shelters in Iraq's northeastern border provinces.