Explosions near a busy subway station in Moscow Tuesday night killed at least nine people and injured 50 more.

Initial news reports suggested one car blew up at about 8:15 p.m. local time, splintering doors and smashing windows at the station in the northeast part of the city.

Witnesses later said they heard two or more blasts.

A police spokesman said on Russian television that 10 people died and more than 20 were wounded, but the death toll was later revised to nine as the injury count climbed to 50.

No one has claimed responsibility, although the Itar-TASS news agency said authorities blamed a woman suicide bomber.

The attack hit a week after two Russian passenger planes crashed minutes apart, killing 90 people.

Officials blamed those explosions on Chechen suicide bombers.

Similar violence has plagued Moscow and other parts of Russia in recent years, including a bomb that tore through a Moscow subway car in February.

A Chechen rebel group took responsibility for the incident, which killed 41 people and injured more than 100.