A British special forces sniper saved the lives of an 8-year-old boy and his father who were about to be beheaded by Islamic State jihadists by firing a shot at the head of the executioner from his position more than half a mile away, a British newspaper reported.

According to the Daily Star, a unit of Britain’s special forces Special Air Service carrying out covert patrols near the Syrian-Turkish border was tipped by an Iraqi spy to the execution site where Shiites accused of being “infidels” were going to be beheaded.

An unnamed military source told the newspaper that “there were several decapitated bodies already lying on the ground” in the village where ISIS members were holding a ‘trial’ in front of a crowd of locals who had been forced to attend at gunpoint.

An SAS ground unit had moved into position just outside the village where the jihadists were beheading ‘infidels’.

The team considered calling in an air strike using a Reaper Drone, but the troops feared many of the innocent civilians who had been forced to watch the executions might also be killed, so they instead decided on a risky long-range kill using the team’s sniper.

“Through binoculars, the soldiers could see that the crowd were terrified and many were in tears,” the source said.

Soon, a man and his young son were pulled from the crowd, blindfolded, and placed on their knees.

“A tall bearded man emerged and drew a long knife,” the source reportedly said. “He began addressing the crowd and slapping the father and his son around the head and kicking them onto the floor.”

On either side of the executioner stood two other fighters who were both armed with AK47s.

ISIS militants had decreed that the little boy and his father must die after branding them “infidels” because they refused to denounce their faith. Right before the knife-wielding jihadist was going to decapitate the father, the SAS sniper shot him in the head using a .50-caliber rifle shot from more than half a mile away.

“Everyone just stared in confusion,” the unnamed source told the Daily Star.

The special forces then used two more bullets to kill the two other members of the terror group who were also taking part in the planned execution.

After the jihadists were killed in the rescue operation that took place last month, the boy and his father were untied and ran away toward the Turkish border.

“It was a good day’s work,” the source told the Star.