MOSCOW - One people were killed and some 94 others missing after a cruise ship carrying 173 sank in Volga river Sunday, the Russian Emergency Situations Ministry said.

"Overall, there were 140 passengers and 33 crew members aboard the double-deck cruise ship. 78 people have been rescued by a passing ship Arabella. One woman died," the emergencies ministry was quoted by RIA Novosti news agency as saying.

According to the ministry, the cruise ship "Bulgaria" sank at 13:58 Moscow time (0958 GMT) near the village of Syukeyevo in the Kansko-Ustinovsky district of Russian republic of Tatarstan.

A helicopter and two rescue boats are currently working at the scene of the incident.

So far, the cause of the sinking is still unknown.