Baku, August 18, Interfax - Unidentified attackers threw the grenade into a mosque, special investigator of the Azerbaijan Prosecutor's Office Rasim Akperov told Interfax.
Three people are killed, nine are injured allegedly including the mosque's imam Gamet Suleymanov.
The grenade was thrown in the mosque's window during evening prayer.
No one was detained on suspicion. The investigation is underway and its preliminary results be known by Monday evening.