'System failed Josh at every level': Man with disability dies after being detained at train station

The family of a disabled man who died after being detained at a train station believe his death could have been prevented.

Josh, 24, suffered a medical episode within a minute of being handcuffed after an altercation with security at Perth Underground Station on Friday night.

9News understands the man became "extremely aggressive" and attempted to "hit one of the officers" at the station.

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Transit security who knew the man and referred to him as JJ asked him to "come up for fresh air" before he was arrested.

Paramedics were called to the station to find Josh unresponsive. They performed CPR before he was taken to the Royal Perth Hospital where he died.

Josh lived with Sotos syndrome, a genetic condition causing physical overgrowth during the first years of life.

"I really feel like the system has failed the family and Josh at every level," disability advocate Samantha Connor said.

"Really we need to have answers right now about how Josh was failed and who Josh was failed by."

The Public Transport Authority declined to comment on what led to Josh being detained.

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