UPDATE: Trains on the Joondalup and Mandurah lines have returned to normal operation.
11.59am: Trains on the Joondalup and Mandurah lines are currently experiencing delays due to a medical emergency.
Trains will continue to run but they will not be running to the regular schedule.
Commuters are being urged to allow extra travelling time and be aware that delayed trains may not connect with timetabled bus and train services.
The medical emergency occurred on the train.
If you require assistance regarding service disruptions or planning your journey, please call the Transperth InfoLine on 13 62 13.