(CNN) -- The suicide bomber who killed four officers and wounded two others in Russia on Tuesday was 25 years old, the state-run Itar-Tass news agency reported Wednesday.
The Interior Ministry in the southwestern republic of Dagestan, where the attack took place, said 11 police officials and three civilians have been killed in attacks this month.
Violence has plagued Dagestan for years as Islamist rebels fight Russian rule over the northern Caucasus region.
An attack on a polling station killed three police officers during Russia's presidential elections Sunday, a police spokesman said.
Tuesday's bombing was in the village of Karabudahkent, near the Caspian Sea coast, according to the state-run news agency RIA Novosti.
CNN's Igor Krotov contributed to this report.