A British Special Air Service trooper killed a member of the Islamic State group with an axe during a rescue mission to free enslaved girls in Syria, according to media reports from the weekend.

The trooper, a member of a joint British-U.S. task force, bashed the ISIS militant with the axe after his gun jammed. The girls being held by the ISIS forces were reportedly being forced to marry the militants. If they refused to do so, they would be punished with dips into acid or crucifixion, the Daily Star reported Sunday.

Intelligence officials first heard about the girls and the punishments being doled out over the summer. Locals of northern Syria, terrified by the atrocities, told the allied forces of the abuse.

Some members of the task force, horrified by the brutal scene once they arrived, reportedly broke down in tears after the relief mission.

The soldiers were flown in by a helicopter into the outskirts of the village where the girls were being held and were backed up by armed drones in the sky. The fighting lasted two hours, during which time Delta Force snipers killed as many as 10 jihadist fighters and Special Air Service fighters killed another 15 gunmen.

These are not the first reports of ISIS fighters abusing women and girls. Earlier this year, for instance, a young woman said she was tortured and treated as a sex slave for nine months before she eventually managed to escape. During that time, she said she was raped by a 60-year-old fighter who she said was high on drugs.

Other reports from earlier this year found Islamic State group fighters were pushing girls to use birth control to maintain their supply of sex slaves as they passed the women amongst themselves. The practice of systematic rape of women is reportedly justified by ISIS fighters through modernized medieval codes.