GlobalPost correspondent Tracey Shelton was filming a feature on the daily life of Syrian opposition fighters when a mundane chore for the men turned into a bloodbath.

Shelton camped with the opposition's Noor Den al-Zenke battalion in their makeshift home on a narrow street in Aleppo. Jokes were being told one morning and laughter was in the air as the men cleaned their post. When an alert came that a Syrian Army tank had been spotted nearby the men dropped their brooms and reached for their weapons.

A Syrian Army tank round explodes in a group of opposition fighters in Aleppo, Syria. (Tracey Shelton/GlobalPost)

In an instant, an explosion tore through their ranks. Shelton shot it as it happened. Of the men at the post, only one survived the blast.

See the GlobalPost's piece to see the entire incident as it unfolded before Shelton's eyes and camera.