By Isabel Hunter
ISIS affiliates in Yemen have beheaded four prisoners before opening fire in a busy market killing at least two men.
The horrific violence was shown in a 21-minute long propaganda video reportedly filmed in Hadramaut, western Yemen.
Labelled as "soldiers of the apostate," four men are forced to kneel and are then beheaded by masked knifemen.
Earlier in the video, wearing desert camouflage traditional clothing, the militants are shown planning attacks before making a night assault on what has been reported as a Houthi or Al-Qaeda outpost.
As dawn breaks, the gunmen go building by building and take ammunition, weapons and what looks like a suicide belt.
Once clear, they blow up the building.
In a later segment, they are shown driving into a market place and walking up to a young man, who the labelled as a 'murtad', in the Arabic subtitles.
The horrific execution is filmed from the point of view of the gunman, and was the camera shows the market again, it is empty.
They were also reported to have killed women in the market place attack, but the video is unclear.
The extensive video also shows recruits training and doing press ups and sit ups as well as fighting exercises with a knife.
Their instructor drills the routine, counting their repetitions in Arabic.
Shared widely by pro-ISIS accounts, the footage was released on February 3.
Yemen has been torn apart by civil war as Iranian-back Houthis fight the Saudi Arabian back government.
The chaos has fostered Islamic extremists Al-Qaeda and ISIS has grown - often carrying out attacks considered too brutal by Al-Qaeda.