Eleven people were killed in a roadside bombing of a minibus on Thursday in the capital of the Russian republic of North Ossetia, news agencies reported.
The regional Interior Ministry blamed the blast on what it called a terrorist act, reported dpa.
"Preliminary investigations into the explosion in the centre of Vladikavkaz point to a suicide bombing," the prosecutor-general's investigative unit working with Russian FSB security services said in a statement.
An explosion hit the crowded minibus as it stopped to let out passengers at the entrance to a movie theatre and market on a main street in the populous southern Russian city, a police eyewitness told Itar-tass.
About 28 people, including one child, had sought treatment after the blast at the local emergency ward, the agency quoted staff at the hospital as saying.
Russian television showed the minibus smoking and charred still as crowds gathered around a police cordon. Bodies were lying in the road outside the twisted van doors.
Vladikavkaz is separated by the 4-kilometre-long Roki tunnel from Georgia's breakaway region of South Ossetia and is the base for Russia's 58th army which deployed into South Ossetia in August to push back a Georgian assault to retake the region.
The regional capital was the target of many terrorist acts blamed on Islamist militants during Russia's war with neighboring Chechnya and tensions in the volatile region have increased amid the conflict across the border in Georgia.