Osama Abu Kuwait, Ihsan Al Shuwaikh, Nehad Al Hussen and Ahmed Ahwakh are the four footballers who have been killed by Daesh. They have also killed the manager of the team and another person who is yet to be identified.
The killing took place in front of hundreds of people, including children, in a square in Raqqa, the capital of what ISIS call the "Islamic Caliphate". Pictures were taken by taken by observers and posted on social media.
The Islamic State has already carried out other attacks on the world of football, a sport which they prohibited two years ago when they took over the city.
On 14 May, they committed a terrorist attack in Balad, the home of the Iraqi Real Madrid supporters' club which killed 16 people. In 2015, the terrorist group publicly shot and killed 13 teenagers for watching an Asian Cup of Nations match between Irak and Jordan.