The footage, which has been shared widely on social media, allegedly shows one of the girls push the top of a spray bottle into the boy’s mouth as he lies on a bed.
The chemical is also apparently sprayed over his genitals in the sickening clip, which involves two girls from East Yorkshire, England who are aged just 15 and 16.
During one part, a girl’s voice can be heard saying the liquid from the bottle has “gone all over”.
Humberside Police have arrested two teenage girls on suspicion of assault.
Detective Inspector Simon Vickers, who is leading the investigation, said: “The boy and his family are being supported by specialist officers and the circumstances of the incidents are being investigated.
“As part of the investigation the girls, who are aged 16 and 15 and cannot be legally identified, have been arrested and are helping us with our enquiries.”
He also warned others against sharing the video, saying doing so may be committing a criminal offence.
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