Gruesome pictures of the executions - which shows children inspecting the bodies of the victims - were posted on a dissedent group's Twitter feed.
In a series of tweets, Raqqa is Being Slaughtered Silently named the victims as Osama Abu Kuwait, Ihsan Al Shuwaikh, Nehad Al Hussen and Ahmed Ahawakh.
They shared pictures of the men in their Al-Shabab kits.Another unnamed man was also executed reportedly a refereem, Daily Mail reports.
Last year ISIS militants executed 13 teenage boys for watching the Asian Cup football match between Iraq and Jordan..
The young football fans had been caught watching the game on television in the Iraqi city of Mosul, which is controlled by the Islamic State.
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