It was the second abortive French hostage rescue since July in the arid Sahel region where Paris says it is at war with al Qaeda in the Islamic Maghreb (AQIM), the North African arm of Osama bin Laden's network.

The two victims were abducted from a bar overnight, bringing to eight the number of French nationals snatched in the African country since last April. They were the first to be seized in the capital Niamey, far from the lawless desert where Islamist militants, rebels and bandits flourish.

French media named the dead men as Antoine De Leocour, working for charity Aide Medicale Internationale, and his friend Vincent Delory, who had just arrived in Niamey to attend De Leocour's wedding. Both were 25 and from Linselles, northeast France.

Their bodies had been flown back to Niamey.

Last July another French hostage, Michel Germaneau, 78, was killed by AQIM after a failed French rescue mission in Mali following his abduction in Niger.