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.

Twenty-nine of the roughly 40 passengers onboard were rescued, with those injured taken to local hospitals according to the BBC.

The submarine, “The Sinbad,” foundered close to the harbor in the city of Hurghada, a popular tourist destination on the Red Sea known for its beaches.

The vessel can descend 82 feet deep in the sea and offers stunning views of the coral reefs and marine life, according to the website for Sinbad Submarines.

The sub has been in operation for several years, with the company boasting itself for owning two of just “14 recreational submarines” in the world.

This is a developing story. Please check back for updates.