Al Qaeda in Yemen posted a video online purporting to show the abduction and execution of 14 soldiers the militants alleged were “apostates”.

The reported attack by the hard-line militant group underscores the security vacuum and potential for sectarian violence in unstable Yemen, a country in political turmoil two weeks after the Houthi rebel group took control of the capital Sanaa.

Posted to Twitter on Sunday and reported by the SITE intelligence monitoring group, the video shows masked militants stopping a bus in the eastern city of Shibam and forcing several of its occupants to lie face down outside.

The video did not indicate when the attack happened.

Displaying the captives’ military IDs before the camera, militants waved pistols and knives, shouting, “God is great!” “God enabled the holy warriors of Ansar al-Sharia to detain 14 Houthi apostate soldiers in Shibam taking part in the military campaign against the Sunnis. Three of them were slaughtered and the rest were shot,” the video said. Al Qaeda’s use of the term “slaughtered” usually indicates being killed by a knife.

Al Qaeda, which also calls itself Ansar al-Sharia, spread in the impoverished Arabian state in the wake of 2011 Arab Spring protests which ousted the country’s veteran leader, split the army and saw the state’s authority disintegrate in rural areas.

Efforts by the military to crack down on the group in recent years have done little to undercut its ability to carry out spectacular attacks on government targets.

The United States has repeatedly bombed Al Qaeda with unmanned aerial drones, while energy rich Gulf states also worry at the deterioration of their strife-torn neighbour’s capacity to keep order.

Yemen’s stability appears even more precarious after Houthi insurgents seized Sanaa on September 21 after four days of fighting which killed 200 people, and government institutions have since functioned at a minimal level.