- 4 updates
Mokhtar Belmokhtar claimed responsibility for the seizure of dozens of foreign hostages at the In Amenas gas plant in Algeria in January in which more than 60 people were killed.
The Chadian claims of his death comes days after Chad's President Idriss Deby said soldiers in Mali had killed another leading al Qaeda commander in the Sahara, Adelhamid Abou Zeid.
French officials said they could not confirm the killing of either Abou Zeid or Belmokhtar.
The death of leading al Qaeda commander Mokhtar Belmokhtar would bring to an end an exhaustive manhunt for a militant branded "The Uncatchable" by the French intelligence.
- Belmokhtar, who Chadian forces claim to have killed in northern Mali, is a one-eyed veteran Islamist guerrilla and smuggler, dubbed "Mr Marlboro" for his illicit cigarette empire.
- He was named by Algerian officials as the man behind January's oil field kidnapping.
- Belmokhtar has been linked to multiple kidnappings of foreigners in North Africa in the last decade, including the taking of 32 European tourists in 2003.
- An Algerian court sentenced Belmokhtar in absentia to a life sentence for his role in the killing of 10 Algerian custom agents in 2007.
- It was claimed he orchestrated January's kidnappings in Algeria, but from a distance, with him based in the rebel-held town of Gao in northern Mali.
- Only last year, Algerian media reports of his death in violence in Gao in northern Mali proved unfounded, only expanding his elusive status.
One of the world's most infamous terrorists is believed to be dead tonight. Chad's armed forces say Mokhtar Belmokhtar was killed by their soldiers in Mali today. He was said to have ordered January's attack on an Algerian gas plant where 37 hostages were killed.
ITV News correspondent Harry Smith has the latest:
One of the world's most infamous terrorists, who claimed responsibility for the death of an engineer from Nottinghamshire, is believed to be dead.
Chad's armed forces say Mokhtar Belmokhtar was killed by their soldiers in Mali.
He was said to have ordered January's attack on an Algerian gas plant where 37 hostages were killed, including Sebastian John from Nottinghamshire.
The Foreign Office has confirmed it is investigating the claims.