A bomb exploded at a market in the southern Russian city of Vladikavkaz on Thursday, killng at least 17 people, including the bomber. (Kazbeg Basayev/Reuters)

A suicide car bomber hit the central market of a major city in Russia's North Caucasus on Thursday, killing at least 17 and wounding more than 130 people, officials said.

The attacker detonated his explosives as he drove by the main entrance to the Vladikavkaz market, according to the Emergency Situations Ministry.

At least 17 people, including the suicide bomber, were killed and 133 were wounded in the explosion, said Alexander Pogorely of the Emergency Situations Ministry's branch in southern Russia. He said 98 of the injured were in hospital, many in grave condition.

Russian President Dmitry Medvedev sent his regional envoy to Vladikavkaz to help co-ordinate efforts to help the victims.

No one has immediately claimed responsibility for the attack.

The market and its surrounding blocks have been the target of several bomb attacks over the past dozen years, in which scores of people have died.

Vladikavkaz is the capital of the Russian republic of North Ossetia. Although it is less plagued by violence than the republics of Chechnya and Dagestan, which are also in the region, North Ossetia has suffered ethnic tensions and frequent terror attacks.

It was the scene of the 2004 Beslan crisis, in which Chechen terrorists took hundreds of hostages at a school — a siege that ended in a bloodbath that killed more than 330 people, about half of them children.

The Vladikavkaz market was bombed in 1999, killing 55 people. Another bombing, in 2001, killed six people, and 11 people died in 2004, when a minibus stopped near the market was bombed.

Russia's North Caucasus region has been gripped by violence stemming from two separatist wars in Chechnya and fuelled by endemic poverty, rampant official corruption and police abuses.

In the Caspian Sea province of Dagestan, officials said Thursday that a hotel employee and another civilian were shot to death by men trying to build a bomb in their hotel room.

Vyacheslav Gasanov, a republican Interior Ministry spokesman, said the shooting took place late Wednesday in the capital Makhachkala.

He said three armed men fled a room in the small hotel after an explosion and opened fire on a hotel clerk and another person who confronted them. Police found several bombs and six grenades in the room, he said.