A Frenchman kidnapped in lawless northern Mali is being held by Al-Qaeda's north African branch, a Malian security official said Friday.
Al-Qaeda in the Islamic Maghreb (AQIM) is the group which killed a Briton in May, the first time the Islamists had executed a Western hostage, according to observers.
The French hostage Pierre Camatte, 61, has "fallen into the hands of armed Islamists in the Sahara" desert after being abducted from his hotel overnight Wednesday, said the Malian official, who spoke anonymously, AFP reported.
"He is being held by the hardline AQIM," he said, adding the group "did not come themselves" to abduct the Frenchman but acted through intermediaries.
The kidnapping prompted France late Friday to urge its citizens to "immediately leave the area due to a new escalation in the terrorist threat."
French people in Kidal, Gao and Tombouctou regions should "head back without delay to the capital," the French foreign ministry said in a statement.
There are around 10 French nationals in the area, according to the foreign ministry.
The French government also urged its citizens to avoid northern Niger, which borders Mali.
Camatte was snatched from Menaka in the Sahel region of northern Mali, more than 1,500 kilometres (1,000 miles) from the capital Bamako.
About 100 kilometeres from the border with Niger, the region is plagued by Tuareg rebels, Al-Qaeda militants and traffickers.
Malian soldiers were drafted in Friday to help in the hunt for Camatte.
AQIM claimed responsibility for killing Briton Edwin Dyer, one of a group of six Westerners kidnapped in the Sahel, on May 31, according to SITE Intelligence, a US-based monitoring group.
The others were released and observers said ransoms were paid in all case, despite denials from the governments concerned.
Camatte is a regular visitor to Mali, where he is involved in cultivating a plant known for its anti-malarial properties, according to the organisation he heads.
The Malian government, for its part, has said the Frenchman settled in Menaka last year where he leads a non-governmental organisation dedicated to fighting malaria in the region and manages a hotel.