In 1995, a chemical weapon containing nerve gas was released in a subway system in Tokyo during rush hour. It remains the deadliest terror attack carried out on Japanese soil.

Many locals remember the attack but don’t realise the close ties WA had to this incident.

Former WA Police Superintendent David Parkinson explains to Perth Today host Simon Beaumont how he was part of the team that tracked the location of the gas used to a station in Leonora, a small town in the Goldfields-Esperance region.

“This was the final bit of the jigsaw that proved that yes, they had been testing and yes, Sarin gas was there,” he said.

Click PLAY to hear more about the investigation.

Image: Supplied