PARIS -- France's defence minister says two French citizens fighting alongside extremists have been detained over the past week in the West African country of Mali.

French authorities have warned that disaffected French radicals could travel to Mali to join al Qaeda-linked forces, and potentially come home with skills to stage terrorist attacks in Europe.

Jean-Yves Le Drian said on Europe-1 radio Friday that two Frenchmen have been detained in Mali since French forces launched a military campaign there in January.

One was detained by Malian police and extradited to France on Thursday, Le Drian said. He said the other was taken prisoner during fighting in northern Mali and will be extradited Friday.

About a dozen French citizens are believed to have travelled to the region to join the extremists.