A French navy sonar team has detected a signal from the second of the two flight recorders from a crashed Egyptian airliner.
Sameh Halawa, director of Sharm el-Sheikh Search and Rescue, said the beep came from a depth of about 800 metres (2,600 feet). "It's a very strong signal," he said today.
The French salvage experts detected a signal from the first flight recorder or "black box" on Tuesday but the French had not foreseen how deep the water would be at the crash site and will now have to bring in new equipment to retrieve the devices.
Relatives of 133 French people killed in the crash took off from Paris, where President Jacques Chirac told them everything would be done to find out why the Egyptian Boeing 737 charter crashed in Red Sea on Saturday, killing all 148 people on board.
"I want to tell all of you in this dramatic moment in the history of our country that all French feel dismay, solidarity and compassion with you," Chirac told the relatives.
"I assure you that everything will be done to determine the cause of this drama," he said before the group of about 100 left on the special flight organised by the French government.
French Foreign Minister Dominique de Villepin will also travel to Sharm el-Sheikh, where he will meet Egyptian President Hosni Mubarak on Thursday and attend the services.
French Ambassador to Egypt Jean-Claude Cousseran said the two services, one on land and one near the crash site at sea, could help the families come to terms with their pain and grief.
The French Navy has sent for more specialised equipment that can reach the wreckage of the plane but French Rear Admiral Jacques Mazars, who is leading the search, said on Tuesday that it could take up to one week for the gear to arrive.
The U.S. Navy recovered a flight recorder in 1996 from a plane that crashed off the Dominican Republic from a depth of 2,195 metres. Professional divers can go to about 250 metres.
The boxes, which record flight data and cockpit conversations, should hold important clues to the crash, which Egypt has said was caused by a technical fault, and not by an explosion or deliberate attack.
France has also said there is no reason to suspect an attack and says it gives little credence to a previously unknown Islamic group's claim to have brought down the plane.
Egypt has defended the safety record of Flash Airlines, operators of the plane, but Switzerland has said it banned the Egyptian company from its airspace on safety grounds. Flash Chairman Mohamed Nour denies the ban was safety related.