Twenty-four Chadian soldiers were killed in an attack by militant fighters in the troubled Lake Chad region, a senior local official said Thursday.
"Troops from a returning patrol were resting when they were attacked by Boko Haram" on Wednesday, the region's deputy governor, Haki Djiddi, told AFP.
"Twenty-four troops were killed, several were wounded and others have scattered into the countryside."
Army spokesman General Azem Bermandoa Agouna confirmed that an attack had taken place at Tchoukou Telia, an island 190 kilometres (118 miles) northwest of the capital N'Djamena, but refused to give any toll.
Troops from "three army sectors have joined the soldiers who came under attack yesterday," Mahamat Fodoul Makay, the governor of Lake province, told AFP.
Lake Chad is a vast area of water and marshland bordered by Niger, Nigeria and Cameroon as well as Chad.
Jihadists from Boko Haram and a rival splinter group, the Islamic State West Africa Province (ISWAP), have been using the region for years as a haven from which to attack troops and civilians.
The Chadian authorities tend to call the jihadists "Boko Haram" regardless of their affiliation.
In March 2020, around 100 Chadian troops were killed in an overnight attack on the lake's Bohoma peninsula, prompting an offensive the following month led by Chad's then president, Idriss Deby Itno.
After pursing the militants deep into Niger and Nigeria, Deby said there was "not a single jihadist anywhere" on the Chadian side of the lake region.
Attacks have continued, however.
In July, 11 Cameroonian troops and a civilian were killed in two attacks in Cameroon's Far North region, the tongue of land that lies between Chad to the east and Nigeria to the west.
Deby was killed in April 2021 during fighting against rebels in northern Chad and was succeeded by his son, Mahamat Idriss Deby Itno, at the head of a military junta.
Boko Haram launched a revolt in northern Nigeria in 2009 before extending its campaign into neighbouring countries.
According to UN figures, more than 36,000 people, most of them in Nigeria, have died and three million have fled their homes.
In 2016, Boko Haram split over its indiscriminate targeting of Muslim civilians and use of women suicide bombers.
Boko Haram said in June that its leader, Abubakar Shekau, had died in fighting with ISWAP, which claims allegiance to the Islamic State group.