MOSCOW (Reuters) - A Russian passenger plane with up to 12 people on board split into three pieces after sliding off a runway and crashing into a highway outside a Moscow airport on Saturday, officials said.

State-run RIA news agency said two people were killed.

A photograph posted on the Internet showed a wrecked plane on a highway outside Vnukovo airport, with smoke billowing from the back end and only a mangled part of the front half visible.

"After a hard landing, the plane split into three pieces," Yelena Krylova, chief spokeswoman for the airport, said in televised comments.

She said there were 11 people on board, all crew, and that nobody was killed, but RIA cited police as saying two people were killed.

An Emergency Situations Ministry official said on television that 12 people were aboard.

The Tupolev-204 passenger plane was operated by the Russian airliner Red Wings and traveling from Czech Republic, Krylova said.

(Writing by Alissa de Carbonnel and Steve Gutterman; Editing by Angus MacSwan)