A shocking video has emerged showing 18 prisoners in orange jumpsuits getting shot in the back of the head from point-blank range in summary executions in Libya. The men, understood to be ISIS fighters, are shown kneeling in four rows and facing away from their killers. 

Executioners can be seen walking up slowly behind their targets before firing a spray of bullets from what look like semi-automatic assault rifles into the backs of their heads before another line of killers repeat the sequence.  

It comes amid tensions between jihadists and Libyan forces in Benghazi after strongman Khalifa Haftar - a former soldier under the Gaddafi regime who has risen through the ranks to commander of the Libyan National Army - declared victory in the eastern city.

It is claimed by the Libyan Express the commander of the eastern Saiqa Force of Operation Dignity Mahmoud Al-Werfalli conducted the massacre. He was also said to have ordered the killings by the Libyan Observer, who reported he had been promoted by Haftar, leader of the Libyan National Army, for his alleged role in killing policemen in May. 

It is understood those killed were ISIS fighters in Libya, according to Al Jazeera, who again claimed it was Al-Werfalli reading the charges before his proteges shoot the detainees dead. In the video, a man can be seen reading from a piece of paper and men in military uniform can be seen walking up to their targets, taking one each, and unleashing a flurry of bullets on the command of their leader. 

The kneeling men fall to the ground face-first, which doesn't stop the gunmen from shooting. Eventually, they turn on their heels and walk back together in a line before a new set of executioners walk forward and kill the next line of prisoners. 

A man in an orange jumpsuit located in the second line appears to fall forward in an attempt to fool the executioners, but he is dragged back onto his knees and callously shot in the head in the second round of killings. 

The video is dated July 17, which means it would have come just days after the UN's human rights spokeswoman Liz Throssell said called for the Libyan National Army (LNA) which controls the eastern part of the country to investigate summary executions of prisoners.

The UN's human rights body and voiced concern at the fate of those still in their custody.

The LNA is pushing to expand its presence in central and southern Libya, where it has been vying for control with forces linked to the UN-backed government in Tripoli and other opponents.

LNA leader Khalifa Haftar has gained ground with Egyptian and Emirati support, and Western states say Haftar must be part of any solution to Libya's conflict

UN human rights spokeswoman Liz Throssell said: 'We are deeply concerned that, after recent fighting in Benghazi, people taken prisoner by members of the Libyan National Army, which effectively controls eastern Libya, may be at imminent risk of torture and even summary execution.

'Reports have suggested the involvement of Special Forces, a unit aligned with the LNA, in torturing detainees and summarily executing at least 10 captured men.'