CAIRO — A recreational submarine taking 45 tourists on an underwater cruise of coral reefs in the Red Sea sank off the Egyptian resort town of Hurghada on Thursday, leaving six Russians dead, the provincial governor said. The remaining tourists, more than two dozen of whom were injured, were rescued, he said.

The cause of the sinking was not immediately known. The Russian consulate said it took place about 0.6 miles offshore.

The submarine was carrying 45 tourists and five Egyptian crew members when it sank, Red Sea governor Maj. Gen. Amr Hanafi, said in a statement, adding that rescue teams were quickly sent.

He said all six dead were Russians, and that 29 of the 39 tourists rescued were injured and taken to hospitals. No one was still missing from the vessel, he said, suggesting the crew had also been rescued.

Hurghada is a major destination for divers, snorkelers and other tourists drawn by the Red Sea’s extensive coral reefs.

The submarine, named “Sindbad,” runs 1- to 3-hour tours, usually cruising at about 20-25 meters (65-80 feet) underwater with panoramic windows on the bottom to give views of the marine life, according to the website of the company that the Russian consulate identified as running the vessel.

The company did not respond to phone calls seeking comment.

Russia’s Tass news agency earlier said the Russian dead included at least two children, citing the country’s consul in Hurghada. The consulate had said all 45 tourists on board were Russian, but the Egyptian governor said they also included Indian, Norwegian and Swedish citizens.

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.