A helicopter carrying 10 French soldiers crashed Saturday off the coast of Gabon in central Africa, the French president's office said. It was not immediately clear whether there were any survivors.
President Nicolas Sarkozy's office said in a statement that "all available means" would be deployed to search for those aboard the helicopter.
The helicopter was carrying out joint military exercises with Gabon when it went down.
In Gabon, French military spokesman Lt. Col. Pascal Carpentier said the helicopter went down off the coast of the country's economic capital, Port Gentil, southwest of Libreville.
It was not known what caused the chopper to plunge into the frigid sea, Carpentier said.
A French naval vessel that was participating in the joint training exercise was helping search for survivors along with a ship from the French oil giant Total, Carpentier said.
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