A submarine carrying Russian tourists sank off Egypt’s Red Sea coast on Thursday, leaving at least four people dead, according to the Russian Embassy in Egypt and local news reports.

The vessel was believed to be carrying about 45 people on a tour in the waters off the coast near Hurghada, a popular resort nearly 300 miles southeast of Cairo.

The embassy reported the deaths in a statement posted on social media, which also said that all the tourists on board were Russian.

Local news outlets reported at least six dead, but the numbers could not immediately be verified. Nine people were injured and were taken to a nearby hospital, and rescue workers pulled 29 people out of the water, the news reports said.

Egypt has a history of problems involving tourist boats. Last November, four people died when a boat carrying 44 passengers sank during a six-day diving trip from Marsa Alam, another Red Sea resort. The trip was supposed to end in Hurghada.

Commercial submarines are popular among tour operators along the strip of holiday towns and resorts for exploring coral reefs.

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