"Unidentified individuals broke into a bus, beat up some of the passengers and took them in an unknown direction" in an incident that occurred in Moscow region on Thursday night, a source in law enforcement service said.
"One of [the assaulters] ordered the driver to move on," the source told Interfax .
The attackers had come in several cars that stopped the bus, which had been traveling from Tula region to Moscow, the source said.
Detectives were at work on the incident site on Kashira Road.
An unconfirmed report said a fight took place on the bus during the journey and that it was after that that the attackers came in their cars.
Interfax has been unable to obtain any official comments from law enforcement services so far.