A tourist submarine taking dozens of people, mainly Russians, to see the Red Sea's coral reefs sank off the Egyptian resort town of Hurghada, leaving six people dead and others injured, two municipal officials said Thursday.

Emergency crews were able to rescue at least 38 Russians, the Russian consul in Hurghada told the country's state news agency RIA Novosti. The report said 14 of them were hospitalized and the rest returned to their hotel.

Russian and Egyptian officials did not immediately say what caused the submarine to sink.

Russia's Tass news agency said five Russians were confirmed dead, including two children. The two Egyptian municipal officials said the total toll was six, but the nationality of the sixth was not immediately known. The officials spoke to the Associated Press on the condition of anonymity because they were not authorized to brief the media.

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Russia's consulate in Hurghada said in a statement that 45 Russians were on board the submarine, "Sindbad," which operated from a hotel of the same name. It was not immediately known how many crewmembers or other tourists were on board, but the submarine has a capacity of 50 people.

Hurghada is a major destination for divers, snorkelers and other tourists drawn by the extensive coral reefs in Red Sea. Several outlets offer tours in submarines with large windows in the bottom to allow groups to view the reefs and marine life, usually cruising at around 20 meters (60 feet) in depth.

In November, a tourist yacht sank in the Red Sea after warnings of rough waters, Egyptian officials said. At least four people drowned, while 33 were rescued.

Tourism is an important sector of Egypt's economy but many tourist companies have stopped or limited traveling on the Red Sea due to the dangers from conflicts in the region.