The crew of a recreational submarine that sank off the Egyptian Red Sea coast killing six Russian tourists and injuring nine other passengers have been questioned by authorities in Egypt amid an ongoing investigation.

At least six people are believed to be dead and another nine injured — six critically — after a tourist submarine sank off of Egypt’s Red Sea coast Thursday.

Egyptian officials say a submarine tourist vessel with 45 passengers and 5 crew sank off the country's popular Red Sea coast, killing at least six people.