LAGOS: Leading human rights groups on Thursday released satellite images claiming to show massive destruction by Boko Haram of two Nigerian towns in what is feared to be the deadliest strike of the Islamists' six-year insurgency.

Amnesty International and Human Rights Watch published separate images of Baga and the nearby town of Doron Baga, on the shores of Lake Chad, in the far north of Borno State in northeast Nigeria.

Hundreds of people, if not more, are feared to have been killed in the attack, Amnesty said, that is thought to have targeted civilian vigilantes helping the army and that reportedly included one woman being killed while in labour.

But Nigeria's military, which often downplays death tolls, said that 150 died and dismissed as “sensational” claims that 2,000 may have lost their lives.

HRW said the exact death toll was unknown and quoted one local resident as saying: “No one stayed back to count the bodies.

“We were all running to get out of town ahead of Boko Haram fighters who have since taken over the area.

“Amnesty's images showed aerial shots of the two towns, which have been hit previously by fighting, on January 2, the day before the attack, and January 7, after homes and businesses were razed.