Two soldiers were killed when suspected Boko Haram fighters loyal to factional leader Abubakar Shekau attacked a military base in northeast Nigeria, security sources told AFP on Sunday.

The twin gun and suicide attacks happened early Saturday evening at Gulumba village, in the Bama district of Borno state.

The use of human bombs is a hallmark of the Shekau faction, which is known to operate in the area. Last month, Shekau released video claiming attacks against troops in Gulumba.

“We lost two soldiers and two more were injured in the attack by the Shekau faction,” says one military source.

“The terrorists came in nine gun trucks with a suicide bomber at about five in the afternoon and attacked the base.”

A second source says the suicide bomber tried to infiltrate the base but was “neutralised” by troops. He also says two soldiers were killed and two others were injured.

“The terrorists faced stiff resistance and were forced to withdraw,” he adds.

Neither source wanted to be identified as they were not authorised to speak to the media.

Attacks by fighters loyal to Shekau have reduced considerably in recent months, which sources attribute to the firebrand leader’s ill health.

Instead, the IS-backed Boko Haram faction Islamic State West Africa Province (ISWAP) has been blamed or claimed responsibility for a wave of attacks against the military since July.

ISWAP split from Shekau’s faction in mid-2016 in protest at the latter’s indiscriminate targeting of civilians, and pledged to hit only “hard” military or government targets.