Commuters are being advised to leave extra time for their journeys today.
The service tweeted: "There are minor delays to service this is due to two trains being withdrawn with faults.
"Please leave extra time for your journey."
Delays on Metro due to withdrawn trains
Passengers on the Metro system are facing delays due to withdrawn trains this morning.
By David Allison
Wednesday, 30th January 2019, 6:05 am
Updated Wednesday, 30th January 2019, 6:33 am