Heavily-armed fighters from the Islamic State West Africa Province, ISWAP, have killed six Nigerian soldiers in an ambush in Borno State, two military sources told AFP Thursday.

According to the military source, the group opened fire on a patrol vehicle Wednesday near Jakana, 30 kilometres (18 miles) from the state capital Maiduguri, killing all the soldiers on board.

“We lost all six soldiers in the ambush, including a colonel,” said the first of two military sources, who both spoke on condition of anonymity.

“The soldiers were on their way to Maiduguri from Damaturu, the capital of neighbouring Yobe state, when the jihadists attacked them around 1620 GMT,” said the source.

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“The gun truck the soldiers were driving in was destroyed,” the second source said.

Following the ambush, the jihadists attacked a military base just outside Jakana in seven trucks fitted with machine guns, engaging troops in an hour-long battle, the sources said.

The attack was repelled by soldiers at the base, with ISWAP fighters abandoning weapons and one vehicle as they fled.

The attacks came hours after a military chief in the northeast warned terrorists in the region to disarm or be destroyed.

Recall that Bulama Biu had told reporters in Maiduguri that the jihadists should lay down their arms “or prepare for a fierce encounter with me”.

However, the army have not officially confirmed the attacks.