A tourist submarine has sunk off the Egyptian coast, with six people believed to be dead and four others in critical condition.

Another nine have been left injured after the tourist submarine sank off the Red Sea resort of Hurghada.

At least 44 people of different nationalities were on board the vessel, unconfirmed local reports have said.

Emergency services rushed to the scene where the tourist submarine, named Sindbad, had sunk. It is understood that the boat went down near the harbour.

A tourist submarine has sunk off the Egyptian coast

Sources have confirmed to local press that the Red Sea Health Directorate and the Egyptian Ambulance Authority have been placed on maximum alert following the incident.

The cause and circumstance of the sinking have not yet been confirmed or reported.

The passengers had been out on a sea trip to see Egypt's coral reefs and tropical fish before the vessel sank.

The nationalities of the people on board is unclear, nor is the ratio of crew to passengers.

Emergency services rushed to the scene where the tourist submarine, named SINDBAD, had sunk (stock pic)

Sindbad has been running tourist trips in the Hurghada area - a hotspot for British and German tourists for several years.

The company allows tourists to travel 25 metres (82 feet) deep in the sea to explore "500 metres of coral reef and its marine inhabitant".

Semi-submarine tours are unlike normal submarines as they do not fully submerge.

Passengers can observe marine life from the lower deck.

In November, a tourist boat named Sea Story in the Red Sea also sunk

In November, a tourist boat in the Red Sea also sunk, leaving 11 dead or missing, including a British couple.

The boat, named Sea Story was carrying 31 tourists of various nationalities and 14 crew members.

Among them were four Britons and two Americans.