NAZRAN, Russia (Reuters) - A blast rocked a cafe in Russia's North Caucasus on Tuesday, killing an unknown number of people, Itar-Tass reported, hours after a suicide bomber killed a policeman in a nearby region.
State television said the cause of the cafe blast and the number of casualties in the city of Pyatigorsk in the Stavropol region were not immediately clear. Interfax news agency said 18 people been taken to hospital after the cafe blast.
The Stavropol regional branch of the Emergencies Ministry could not be immediately contacted for comment.
In North Ossetia earlier, a suicide bomber blew himself up after approaching a checkpoint on a road near the border with Ingushetia province, a North Ossetian police official said.
He said one officer was killed. A duty officer at the regional Investigative Committee, a branch of the prosecutor's office, said three more officers were injured.
The Kremlin is struggling to contain an Islamist insurgency in its mainly Muslim North Caucasus. The Stavropol and North Ossetia regions are both majority Russian Orthodox Christian.
Beslan, where Islamist militants seized a school in a 2004 attack that led to more than 330 deaths, more than half of them of children, is in North Ossetia.
Pyatigorsk was chosen by the Kremlin late last year to be the administrative centre of the new North Caucasus Federal District, a regrouping of the region's provinces to include Stavropol in a bid to tackle growing violence.
At least five people were killed and 20 injured in May when a bomb exploded outside a theatre in the city of Stavropol just before the start of a Chechen dance show. No one claimed responsibility for the attack.
Tuesday's suicide attack was in North Ossetia's Prigorodny district, the site of a territorial dispute between ethnic Ossetians and Ingush that erupted into fighting in 1992 and remains a source of tension.
(Writing by Steve Gutterman and Amie Ferris-Rotman; editing by Andrew Roche)
