MOSCOW —
A suicide bomber has killed four police officers in the capital of the Russian region of Chechnya as thousands gathered to celebrate a local holiday.
Police were searching a man at a security checkpoint outside a concert hall when he detonated the explosives. Russia's Interfax news agency reports that the police blocked the bomber from entering the venue.
After two separatist wars in the 1990s, Chechnya has become more stable under pro-Kremlin leader, Ramzan Kadyrov, whose birthday was also being celebrated Sunday.