In a major goof up, al Qaeda-linked rebels in Syria beheaded a wounded fellow extremist after assuming he was a supporter of President Bashar al-Assad, media reports said on Friday.
In a gruesome video posted online earlier this week, two men claiming to be members of Islamic State of Iraq and al-Sham (ISIS), are shown displaying the head of a bearded man.
In the film, the two men -- one of whom is holding a knife -- claim the executed man was a member of the Iraqi Shia militia fighting for President Assad.
However, according to The Telegraph, following the publication of the video online the beheaded man was recognised as Mohammed Fares, an anti-government fighter and member of Ahrar al-Sha, a group allied to ISIS.
Reports claim that Mohammed Fares was admitted to a makeshift hospital where ISIS fighters apparently misunderstood when he shouted the names of two revered figures in Shiite Islam.
The Sunni opposition assumed that he was a government fighter, The Independent reported.
"We call on God to accept Mohammed Fares into his Kingdom and to forgive his brothers that sought to rid us of the enemies of God and our enemies," Omar Al-Qahatani, a spokesman for ISIS group, was quoted as saying in a statement.
Qahtani said the incident would be investigated by the appropriate judicial authorities.
After two years of unrest in Syria, many say the country is facing the worst humanitarian crisis in the modern history of the Middle East.
Some four million people have been internally displaced, and the death toll is estimated to be over 100,000 people.