Two people were killed in North Caucasus region of Dagestan overnight when a blast ripped through their car, which was believed to have been carrying explosives, Interfax news agency reported on Thursday.
Interfax quoted police as saying the car blew up near a village in western Dagestan and that a third person was in hospital with serious injuries.
"According to preliminary information, an explosive device transported in the car spontaneously went off," a police spokesman said.
On Wednesday, bombs killed at least 12 people in the Dagestani town of Kizlyar, two days after deadly attacks in Moscow that authorities linked to insurgents from the region.
On Monday, Moscow was hit by twin morning rush-hour blasts that killed 39 people. Authorities blamed female suicide bombers with connections to the North Caucasus.
Car blast kills two in Dagestan: Russian agency
Two people were killed in Dagestan overnight when a blast ripped through their car, Interfax news agency reported.