Police arrested three Beersheba teens Tuesday suspected of sexually assaulting a 15-year-old girl with autism.

Based on an initial investigation, a group of at least seven teenagers allegedly forced the girl to go to the home of one of the youths in Israel’s south last month. There, two pinned the girl down and sexually assaulted her against her will, while the other boys looked on, according to a Channel 2 report. It was unclear why the remaining suspects had not been detained.

The three arrested are 15-years-old. One of them took video footage of the incident on his phone and sent it to friends at their school, according to the report.

“This is a shocking case of exploitation of a helpless individual — forced sexual intercourse with a minor who was probably unaware of her actions,” a source close to the investigation told Channel 2.

Boaz Kenig, an attorney for one of the accused teens, acknowledged the disturbing nature of the crimes, but denied any involvement by his client, saying he was cooperating fully in the investigation.

Police on Wednesday requested that the remand of the teens be extended, a police statement said.