Reports from southern Somalia say French commandos have attempted to rescue a French security advisor who had been kidnapped in Mogadishu in 2009.

Residents in the town of Boulmarer say they heard gunfire and explosions shortly after spotting helicopters in the air. They also report seeing a number of casualties after the clash, although the identities of the dead are not clear.

It is also not known if the hostage was rescued.

French officials have not commented publicly about the operation, which followed French military intervention in Mali. A spokesman for the al-Shabab militant group says they killed several commandos, and that the rescue operation failed.