A parked car exploded outside a cafe in southern Russia on Tuesday, injuring at least 20 people, police said.
The explosion occurred just outside the cafe in downtown Pyatigorsk, a city in Russia's North Caucasus, said Stanislav Belyayev, a spokesman for the Stavropol regional police. The wounded were cafe customers and passers-by, he said.
Belyayev said the explosion appeared to be a deliberate terror attack, although an official probe had only just started.
Bombings and other attacks occur regularly in the North Caucasus, where violence has spread following two separatist wars in Chechnya. While most attacks are carried out by militants targeting police and other officials, some are the result of business disputes.
Hours earlier today, a suicide bomber killed a police officer and wounded two others in the neighbouring North Caucasus province of North Ossetia.
The attacker blew himself up at a police checkpoint on the outskirts of the provincial capital, Vladikavkaz, regional police spokesman Aslan Dzgoyev said. The bomber, who died in the explosion, was accompanied by two other men. One of them was captured after police shot and wounded him, while the other escaped.