Winan Bin Yousef, more commonly known by his nom de guerre Jalaluddin, was arrested in Niger near the border with Algeria, the report said.
Michel Germaneau, a 78-year-old French hostage being held in Mali, who was executed in July 2010. The leader of Al-Qaeda in the Islamic Maghreb (AQIM) said Germaneau was killed in revenge for a failed rescue raid in Mali in which six militants were killed.
Bin Yousef, a Mauritania native, is considered a prominent figure in AQIM, an offshoot of Al-Qaeda.
The El-Khabar report said Bin Yousef sought medical care in Algeria and aimed to cross the border using false documents.
He was considered one of the first Mauritanians to enter Al-Qaeda when he jointed the group in 2004..