Attackers shot Vali Haji Gholizadeh late Monday outside his home in the town of Khoy in northwestern Iran.
Authorities have detained four suspects.
The Iranian news agency ISNA quotes a provincial official as saying no one has claimed responsibility for the killing. But Mohammad Ali Mousavi, who heads the region's justice department, says he suspects the Kurdish separatist group, Party of Free Life in Kurdistan, or PJAK. Mousavi said the group had threatened the prosecutor in recent days.
Eastern Kurdistan is under Iranian occupation.
There are currently 17 Kurdish political prisoners who are awaiting execution.
1. Ms. Zeynab Jalaliyan
2. Habibollah Latifi
3. Shirkoh Moarefi
4. Farhad Vakili
5. Farzad Kamangar
6. Ali Heydariyan
7. Hossein Khazari
8. Rashid Akhkandi
9. Mohammad Amin Agushi
10. Ahmad Pouladkhani
11. Saeed Sami Hosseini
12. Saeed Jamel Mohammadi
13. Rostam Arkiya
14. Mostafa Salimi
15. Anwar Rostami
16. Hassan Talai
17. Iraj Mohammadi
The French news agency, AFP, initially quoted an Iranian interior official, Fakhrali Nikbakht, as saying the PJAK had claimed responsibility. But Iranian media quoted other government officials who said no group had claimed responsibility for the attack.
