A motorboat carrying 15 people struck a larger ship and sank in the Neva River in central St. Petersburg early Wednesday, emergency officials said.
Twelve people were hospitalized with various injuries.
The motorboat with 13 passengers and two crewmembers overturned after colliding with a dry-cargo vessel around 2 a.m., the city's branch of the Emergency Situations Ministry said in a statement.
Some people managed to reach the riverbank themselves, while others were picked up by passing boats.
All the people were rescued in a timely manner, and the injured were rushed to the hospital, the statement said. An investigation has been opened.