France's top military officer says it is "probable" that a top commander in al-Qaida's North African branch was killed in northern Mali last week.
Admiral Edouard Guillaud, the head of France's joint chiefs of staff, said the killing of Abdelhamid Abou Zeid cannot be confirmed because his body has not been recovered.
He told Europe-1 radio Monday that it would be "good news" if Abou Zeid is dead.
The nation of Chad said Friday that its troops in northern Mali killed Abou Zeid, a leader of al-Qaida in the Islamic Maghreb linked to the kidnapping of several Westerners.
French and Algerian news reports said authorities are trying to match DNA from Abou Zeid's relatives to what is believed to be the militant's body.
Later Monday, a news website in Mauritania that has close contacts with Islamist extremists, said an Islamist source is confirming that Abou Zeid is dead.
But the website said the unnamed source is denying reports that another militant, Mokhtar Belmokhtar, has been killed. Belmokhtar is an al-Qaida-linked militant who claimed responsibility for the deadly siege at an Algerian natural gas plant in January.
Chad says its forces killed Belmokhtar Saturday when Chadian soldiers overran a militant base in the mountains of northern Mali near the Algerian border. The killing has not been independently verified.
Chadian forces are assisting in the French-led offensive to drive Islamist militants out of northern Mali.
British Foreign Secretary William Hague visited Mali on Monday to meet with that country's president, prime minister and foreign minister. He reiterated London's support for Mali's fight against Islamists, including through an EU training mission. However, he said Britain will not send troops to Mali.