MOSCOW, December 25. /TASS/. At least four people were killed and eleven others were wounded as the bus plunged into a pedestrian underpass near a metro station in western Moscow, a source in the city emergencies services said.

The bus plunged into a pedestrian underpass near the Slavyansky Bulvar metro station at 2.50 p.m. Moscow Time when a large number of people were there.

The accident has nothing to do with a ramming attack, a law enforcement source told TASS. "Terror attack is ruled out. The driver failed to control his vehicle," the source said.

The driver has been detained. Police are considering two theories: the driver either failed to control his vehicle or a technical malfunction.

The Interior Ministry’s press service in Moscow has confirmed the death of four people in the accident. One person has been rescued and is in a serious condition now.

The driver has been working for the company for 17 years and received his license more than 30 years ago.