The US Secretary of State, John Kerry said the killing of civilians in northeastern Nigeria by Boko Haram over recent days, was "nothing less" than a crime against humanity, reports VoA.

Speaking a day after satellite images were released by Amnesty International, showing the destruction of buildings in two towns targetted by Boko Haram fighters, Mr Kerry said that the group was "one of the most evil and threatening terrorist entities on the planet today."

Members of the African Union are set to meet next week, to discuss setting up joint military action against Boko Haram in Nigeria.

Ghana's President John Mahama called on African Union leaders to initiate a "specific plan of action” to "deal permanently" with the Islamist militant group, days after they were accused of massacring up to 2,000 people in one attack.

Earlier this week, Amnesty International released satellite imagery showing the scale of the attack on the towns of Baga and Doron Baga, in what it termed the “deadliest massacre” by Boko Haram.

"This has to end. We have to make this terror end," said Mahama. "We must find a way to act together to share information, to synchronise our strategies, to pool our resources in order to rid the entire African continent of terrorism.”

As many as 500 asylum seekers are on hunger strike in Manus Island detention centre and a further 20 of them have reportedly sewn their lips shut in protest at their living conditions, according to the latest reports.

In another act of protest, an Egyptian Christian man swallowed razor blades and collapsed, reported the Guardian, as up to half of the detention centre’s population were refusing all food and water.

One of those being detained told the Guardian,

“Frustrated refugees are tired of being mistreated and not heard after 18 months in inhumane detention [and have] decided to act for the last time.”

“We’ve been very clear with the highest levels of the Government of Pakistan that Pakistan has to target all militant groups, the Haqqani Network and others, that target U.S. coalition and Afghan forces and target people in Pakistan and elsewhere. And Pakistan has made it very clear that they intend to do so.”