“We lost 92 of our soldiers, non-commissioned officers and officers,” the president said of the attack overnight on Sunday in Boma.
“It’s the first time we have lost so many men,” he added, after visiting the site of the incident in Lac province, which borders Niger and Nigeria.
The attack on soldiers on the Boma peninsula lasted at least seven hours and reinforcements sent to help out were also hit, one soldier told AFP news agency.
He said 24 army vehicles were destroyed, including armoured vehicles and Boko Haram carried off weapons stolen from the military in speedboats.
“The enemy has hit at our defences hard in this zone,” a senior officer said.
The attack is part of an expanding armed campaign in the vast, marshy Lake Chad area, where the borders of Cameroon, Chad, Niger and Nigeria converge.