The Syrian rebel group Jaysh Al-Islam has recently released a video featuring 18 members of the Islamic State in Iraq and Syria (ISIS) being executed in cold blood.

The footage, meant to mimic ISIS’ own professional execution videos, shows 18 men (allegedly ISIS militants) in full black, chained together with hand and ankle shackles and metal balls, being led by their executioners; rebel fighters wearing the orange prison clothes that ISIS’ victims usually dress in before being executed.

The Saudi-backed Jaysh Al-Islam says ISIS militants are being executed to revenge the beheading of three members last week, accusing the world-terror group of allaying with President Assad and the Shiites against Sunni Muslims.

The nearly 20-minute video also contains lengthy confessions by ISIS militants that they have never fought the Syrian Army, rather focused their attention on battling anti-Assad rebel groups. On what conditions those militants made their confessions and how authentic they are remains unanswered.

Last week, a video featuring ISIS militants executing 12 members of rival rebel groups has gone viral on social media networks. At least 3 of the 12 are believed to be from Jaysh Al-Islam, 1 from Jabhet Al-Nusra.

Just like ISIS’ controversial footages, the film uses high-quality filming techniques and is shot from different angles.