Girls who violate the strict dress code imposed by Isis in Raqqa are reportedly being placed in a cage with skeletons as punishment.
A 19-year-old girl was placed in the cage "with some skulls", according to activists from Raqqa is Being Slaughtered Silently (RBSS).
She later passed out and was taken to hospital after four hours in the cage, the group of citizen journalists, which exposes human rights abuses in the Syrian capital of Isis, said.
A second girl was later placed in the cage, near Al Nour mosque, for violating the dress code.
RBSS have previously reported on crucifixions, executions and general life in Raqqa.
Earlier this month, they reported on Isis mock crucifixions of at least ten people in just two days.
Isis released the names and photos of eight men, saying it had killed them and crucified their bodies on charges of robbery and corruption.
The group recently suffered one of its biggest military defeats in Palmyra, which was seized by regime forces backed by Russian air strikes.
Iraqi authorities say the terror group is increasingly relying on car dealerships and fish farms to offset their diminishing oil income.
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