"We carried out several air strikes on enemy positions that resulted in many dead and wounded," Deby told reporters in the Lake Chad region, without giving specific numbers.

Deby, who gave an interview in full military fatigues, said he had "personally" launched the counter-attack against Boko Haram, which targeted the Chadian army in an attack last month in the western region, close to the border with Nigeria.

The Chad government had vowed to "obliterate" Boko Haram when launching its operation in late October after the jihadists killed around 40 people and wounded dozens more in a raid on a military garrison.

The operation "aims not only to secure our peaceful population" but also to "hunt down, root out and obliterate the capability of Boko Haram and its affiliates to cause harm", interim Prime Minister Abderahim Bireme Hamid told reporters last week.

In a vast expanse of water and swamps, the Lake Chad region's countless islets serve as hideouts for jihadist groups, such as Boko Haram and its offshoot Islamic State in West Africa (ISWAP), who carry out regular attacks on the country's army and civilians.

Chad and its neighbours Nigeria, Niger and Cameroon set up a multinational force of some 8,500 soldiers in the area in 2015 to tackle the jihadists.

Boko Haram launched an insurgency in Nigeria in 2009, leaving more than 40,000 people dead, and the organisation has since spread to neighbouring countries.

In March 2020, the Chadian army suffered its biggest ever one-day losses in the region, when around 100 troops died in a raid on the lake's Bohoma peninsula.