An explosion tore through a Moscow apartment building before dawn Sunday, injuring five people and forcing police to evacuate the rest of the 12-story building, Russian news media reported. Authorities said the blast may have been caused by a gas leak.
The explosion struck at about 4:20 a.m., destroying several apartments in the building, news agencies said. The radio station Echo of Moscow reported five people were injured.
Officials at the Emergency Situations Ministry could not immediately be reached for comment.
The blast occurred in a building on Chertanovsky Street, a thoroughfare on the southern edge of the city, and appeared to have been centered in a fourth-floor apartment.
The cause of the blast was not immediately determined, although authorities said initial indications were that it was caused by gas. Natural gas explosions in Russia's often-shabby apartment buildings are not uncommon, but fears about terrorism are running high in the wake of a series of explosions that authorities blame on Chechen separatist rebels, including a bombing last month on the Moscow subway that killed 41 people.
Some 300 people died in apartment explosions in September 1999 that officials blamed on the rebels. Following the explosion, police and emergency workers began evacuating other residents of the building. Dozens of city buses were brought to the scene to hold the evacuees, reports said.
Security concerns have also been high in the Russian capital ahead of March 14 presidential elections, with authorities speculating that terrorists could launch attacks to disrupt the voting or tarnish incumbent President Vladimir Putin, who is expected to win.
On Friday night, a bomb exploded at a building in central Moscow that reportedly was being converted into a Jewish school. No one was injured.