Idlib Syria helicopter
Images of the downed helicopter and its wounded crew were posted online Twitter

Anti-government rebels in the Syrian province of Idlib have posted a series of gory images and videos purporting to show the crash landing of a helicopter carrying government forces 10km from Maarat al-Numan.

Warning: Graphic images

This video apparently shows the pro-Assad helicopter making a crash landing

According to the rebel group claiming responsibility, Ajnad al-Sham, four of those aboard were captured alive and one died. One photograph appears to show one of the men being summarily shot dead. Another man is unaccounted for.

The rebels, including members of the al-Qaeda-linked Nusra Front, claim the helicopter was carrying barrel bombs and came from the same air base that attacked the town of Sarmin with chlorine gas a few days ago, resulting in the death of six civilians. The claims of the militants have not been verified.

One video posted online reportedly shows the helicopter descending fast, after either suffering a mechanical failure or sustaining damage after being shot by rebels.

Other videos show the crew in severe pain. In one video a man is reported as saying in Arabic: "Give him aid, we are Muslims not like [these] pigs." Another man then holds a stethoscope to the man's chest.

Following the incident activists reported the bombing of rebel-held areas by pro-Assad forces.

The crash and subsequent capture of the helicopter crew represents a serious problem for President Assad, particularly after the burning alive of Jordanian pilot Moaz al-Kasasbe in January.

Ominously, in one Tweet a pro-rebel activist writes: "#Nusra | Incha Allah this pilot & his crew will get there deserved punishment in the streets of #Sarmin #Idlib".