A grenade exploded in an apartment in a southern Russian city on Thursday, killing two people, the Federal Security Service said.
The ITAR-Tass news agency, citing the Security Service, said a man detonated the grenade, killing himself and a woman. ITAR-Tass said that no one else was injured.
The Interfax news agency, citing emergency officials, also reported that the explosion was caused by a grenade.
On Tuesday, a car bomb exploded near a Vladikavkaz market and adjacent to a bank, killing two people and injuring at least nine. Authorities said they had not yet determined whether that explosion was linked to the war in neighboring Chechnya.
Vladikavkaz is the capital of the province of North Ossetia, to the west of Chechnya, where rebels and Russian forces have been fighting since 1999. The fighting occasionally spills into neighboring areas, but Vladikavkaz has also been the site of shootings and bombings connected with local crime groups.