Moscow (CNN) -- Four people face criminal charges in connection with the sinking of a Russian ship Sunday in which scores of people died, federal investigators said Tuesday. Both Svetlana Inyakina, general director of Argorechtur, the company that rented the cruise boat "Bulgaria," and Yakov Ivashov, a manager at the Kama River Register, have been detained, Russia's Investigative Committee said. They are charged with providing services that do not meet safety standards which resulted in multiple deaths, and if convicted could be jailed for up to 10 years. Criminal charges are also being brought against the captains of two ships which are accused of passing the sinking boat without stopping to help the people in the water, the committee said. They could face heavy fines or up to three years in prison.
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The criminal charges brought against four people over the sinking carry heavy penalties
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PM Vladimir Putin promises compensation for families of the dead and those injured
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President Dmitry Medvedev declares Tuesday a national day of mourning
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The ship was overloaded and not licensed to carry passengers, prosecutors say
@placeholder is observing a day of mourning Tuesday with church services taking place all across the country, flags flying at half-staff and national television canceling all entertainment programming in the wake of what Russian media are calling the most devastating river accident in the country's history.