The authorities in Egypt say they are investigating the circumstances that led to the sinking of a tourist submarine off its Red Sea coast on Thursday.
At least six people on board died in the tragedy.
Rescuers say the toll may rise because because several of the 29 injured are in critical condition.
Red Sea governor Amr Hanafy said the cause of the incident is being investigated but confirmed that the company under which the submarine was registered was issued with a valid licence.
Its crew was also issued certificates proving their competence to run the boat.
It appeared that the weather was quite calm with no sign of any rough waters.
Some 40 passengers were on board the submarine Sindbad when it went down close to the shores of the city of Hurghada in Egypt in the early hours of Thursday.
The boat has been used to run regular trips for tourists flocking to Egypt every year.
The Russian embassy in Cairo has issued a statement confirming that all tourists on boat the boat were Russian citizens.
WN/as/APA