The execution of a 15 year old coffee vendor in the streets of Aleppo earlier this week has sparked rage among residents and galvanized moderate Syrian rebels to condemn the radical Islamist factions that have taken over the city.

Muhhamad Qatta' was first beaten and tortured, and then shot to death publicly in front of a crowd near his coffee stand after he refused to give someone a free cup of coffee. "Even if Muhammad came down from heaven, I would not give you a coffee on credit," he told the person. Three men, including the one who asked for the coffee, declared he had committed blasphemy by insulting the prophet of Islam, Muhhamad, according to a witness. The boy was then kidnapped by the men, and returned shortly after to the site, where he was summarily shot in the head and the neck. His executors announced to the crowd the same fate awaited anyone else found guilty of a similar transgression.

Witnesses said two of the men spoke classical Arabic – but the boy’s horrified parents, who were in the crowd at the time, said the third was a resident of Aleppo, according to the BBC.

Louay Meqdad, a spokesman for the Free Syrian Army (FSA), called the public killing of the young teen by Al Qaeda-linked rebels an act of terrorism. He emphasized the group responsible was not connected to the FSA, according to the pan-Arabic Aljazeera news network, and said the perpetrators should turn themselves in to the "legitimate authorities" in Aleppo.

The question, however, is, who the FSA considers to be the "legitimate authorities" in Aleppo. The city is currently controlled by the same radical Islamist rebel faction that earlier in the year declared the city would become a separatist Shari’a (Islamic law) state – and which sometimes fights together with the FSA when it becomes necessary to unite to fight off Syrian government forces.

The FSA and the UK-based Syrian Observatory for Human Rights have both blamed the "Islamic State of Iraq and al-Sham" – a group formed as the result of a merger between Syrian Islamists and Al Qaeda in Iraq.

The Local Coordination Committees (LCC) activist network in Syria also condemned the murder, calling it a "heinous crime."

As the secularist groups attempt to distance themselves from the execution, residents in Aleppo told reporters they found little difference between the brutality of radical Islamists shooting a teenager to death for a flippant remark about Muhammad, and the brutality of government troops doing the same more than two years ago over an Arab Spring slogan scrawled on a wall – the one that ignited the uprising in the first place.