Clashes between rival jihadist factions in northeastern Nigeria have left some 200 dead in the volatile Lake Chad region, an intelligence source, a militiaman and a jihadist source told AFP on Monday.

Fighting between Boko Haram jihadists and their rivals from the Islamic State in West Africa (ISWAP), which is often fueled by ideological differences and a struggle for territorial control, broke out on Sunday in Dogon Chiku, on the shores of Lake Chad, according to the same sources.

"According to the figures we have obtained, approximately 200 ISWAP terrorists were killed in the fighting," Babakura Kolo, a member of an anti-jihadist militia that supports the Nigerian army, told AFP.

A former Boko Haram jihadist, who has renounced violence but is monitoring jihadist activity in the region, confirmed that "around 200 ISWAP fighters were killed in the fighting" and several of their weapons were seized.

Boko Haram has lost four fighters, according to the ex-jihadist, who asked to be identified by his first name, Saddiku, and lives in Maiduguri, the capital of Borno State, the epicenter of the insurgency.

A source within Nigerian intelligence operating in the region indicated that they were closely monitoring the consequences of the clashes, which they said had resulted in "more than 150 deaths".

"We are aware of the fighting, which is good news for us," the source added.

ISWAP and Boko Haram have been engaged in violent battles for control of territories since their split in 2016, due to ideological differences, particularly around Lake Chad.