A seemingly innocuous codename chosen by French special forces in south-east Afghanistan caused alarm among US troops searching for Osama Bin Laden.
Mistaken identity: The crustacean became "Omar"
A newly arrived French commander picked "homard", meaning lobster, as an alias, the newspaper Liberation reports.
He did not realise that it sounds like Omar, the first name of the Mullah who led the Taleban and is now on the run.
Concerned US intelligence services monitoring French communications raised the alarm and the codename was changed.
The French commander, a navy commando, was described as an expert on the Muslim world.
The incident, said to have happened in July 2003, marked the start of French special forces' involvement in operation Enduring Freedom, the US-led action to find the al-Qaeda leader.
The presence of more than 200 French troops in the area has only just been acknowledged by Defence Minister Michele Alliot-Marie.
"Our men are well established and are very well acquainted with the terrain," she told the weekly magazine L'Express.
Lobsters were among the many things the former Taleban regime banned, which included recorded music, shorts and kites.