RT NewsTwin blasts hit Makhachkala, the capital of the southern Russian republic of Dagestan, according to local police. Sixteen people were injured, among them four police officers.
Those injured have been taken to hospital, but none are thought to be in a life threatening condition.
The first explosion occurred when a grenade launcher was fired at the second floor of a restaurant, said a spokesman for the Dagestani police as cited by Itar-Tass.
The second blast came from a parked car near the restaurant. Police said that the explosive device that detonated near the restaurant was not packed with shrapnel.
“An investigative team is currently operating at the scene establishing the circumstances of the incident. Among the possible causes may be a criminal rivalry,” a security source told RIA Novosti.
The southern Russian republic, together with neighboring Chechnya and Ingushetia, has suffered from the continuous threat of terrorism against the civilian population.
Shootouts between Russian law enforcement officers and militant groups are common in the region. Among the latest incidents, three officers were killed in Dagestan on Wednesday. The special rapid response unit officers were ambushed as they were checking information about the location of a group of militants, a district police official told Itar-Tass.