Former AFL star Ben Cousins has reportedly been hospitalised after police were called to an incident on Perth's Canning Highway.
He was eventually chased by police into bush near the Kwinana Freeway before being taken by ambulance to Fiona Stanley Hospital.
Cousins was reportedly incoherent and a witness told reporters at the scene that he attempted to jump on the back of someone's motorcycle, almost causing the driver to lose control.
"He was really lost, confused, making no sense at all, one witness said. Seven or eight cop cars turned up left, right and centre. They even had the helicopter above us," the witness told Seven News.
Another witness described more bizarre behaviour from Cousins in the lead up to his altercation with Western Australian police.
"He looked like a bit of a mess. His jeans were riding really low and he was running and sweating heaps," the witness told Seven News.
The 2006 West Coast premiership player and 2005 Brownlow Medallist reportedly spent three hours with window washers just off the freeway before he decided to act as a traffic patrolman.
Cousins has a long history of drug and alcohol problems dating back to 2006 when he infamously fled a booze bus, also on the Canning highway, leaving his then girlfriend Samantha Druce in his car to face police.
This latest incident is one in a long line for the former AFL star, who in 2015 was charged with reckless driving and also assessed at a mental health facility in Perth after being caught behind secure fences at Perth's Special Air Service Regiment.