More than 40 farmers and fisherman have been killed in a brutal series of executions by suspected extremists in Nigeria.

The sickening atrocity is thought to have been carried out by fundamentalist group Boko Haram after farmers resisted attempts to extort money.

Victims were reportedly beheaded and had their throats slit after being rounded up by militants.

Around 20 more people are missing, authorities have said.

According to reports in Nigeria, the massacre was carried out in revenge after a Boko Harem gunman was captured after he demanded money and food.

Terror group Boko Haram is suspected of being behind the attack

The attack happened in Garin Kwashebe, Borno state, in the north of the country.

Heartbreaking pictures show a mass burial being carried out following the mass killings.

As news of the massacre emerged, Nigeria's President Muhammadu Buhari said: “I condemn the killing of our hardworking farmers by terrorists in Borno State.

"The entire country is hurt by these senseless killings.

"My thoughts are with their families in this time of grief."

It is claimed that farmers were attacked after a Boko Haram gunman was captured

Ahmed Satomi, a member of the House of Representatives, said at least 44 burials were carried out today.

He said: “Farmers and fishermen were killed in cold blood.

"Over 60 farmers were affected, but we only have so far received 44 corpses from the farms."

He continued, the New York Post continues: “A lone gunman, who was a member of Boko Haram came to harass the farmers by ordering them to give him money and also cook for him.

"While he was waiting for the food to be cooked, the farmers seized the moment he stepped into the toilet to snatch his rifle and tied him up.

"They later handed him over to the security. But sadly, the security forces did not protect the courageous farmers."

No group has yet admitted responsibility for the massacre.