A video showing a young man being beaten up by two men dressed in army uniform in a Syrian detention centre has been posted online.

The leaked video, which has not been independently verified, was said to have been filmed in a detention centre in the town of Kafranbel, activists said.

The video shows a young man in his underwear being assaulted by two men in army uniforms.

In the footage they repeatedly slap the man in the face. One of the officers then strikes him with what seems to be a cable.

The prisoner falls to the floor but the attack continues with his assailants kicking him in the back and face and stomping on him.

It is not known who he is or why he was arrested but the officers accuse him of being a traitor for standing against the Allawites, Syria's ruling Shia minority.

"So you want your freedom?" one of the officers asks the man.

"So you are against the Alawites?" the second officer can be heard asking.

Systematic torture

The man bears torture marks all over his body.

IBTimes UK has aired only a portion of the video as the remainder is too graphic.

It came a few days after Human Rights Watch said the Syrian regime has at least 27 detention centres where torture is systematic.

In a report entitled Torture Archipelago: Arbitrary Arrests, Torture and Enforced Disappearances in Syria's Underground Prisons since March 2011" , HRW said: "Interrogators, guards and officers used a broad range of torture methods, including prolonged beatings, often with objects such as batons and cables, holding the detainees in painful stress positions for prolonged periods of time, the use of electricity, burning with acid, sexual assault and humiliation, the pulling of fingernails, and mock execution."

The group said that state-sanctioned abuse amounted to war crimes and should be investigated by the International Criminal Court in The Hague.

UN human rights chief Navi Pillay warned that both sides to the Syrian conflict appear to have committed war crimes and both the government and rebels werer receiving more arms.

Disappearance of Noura Qanawati

The Syrian Network for Human Rights (SNHR) has also launched an appeal after Aleppo graduate Noura Qanawati disappeared in custody.

The network said officers from the Syrian Air Force Intelligence Unit raided her home on 1 July, arrested her and seized her computer.

When her father, Fateh Qanawati, went to the intelligence unit branch the following day he was told by the chief officer to forget his daughter ever existed, SNHR said.