The boss of Metro operator Nexus has issued a statement explaining what went wrong yesterday
Writing on the company's website, Nexus managing director Tobyn Hughes said: "As you will probably know Metro was unable to provide a service for most of yesterday, Sunday 29 October, across the whole system. This is almost unprecedented in Metro’s history and is a serious failure for which I want to apologise.
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"This was due to a major and sudden fault within the substation which provides high voltage power to the Metro depot in South Gosforth. This happened just before 05:00 yesterday and meant that, without power, no Metro trains could leave the depot.
"Metro staff attempted to shunt Metrocars out of the depot using a maintenance locomotive but this proved a very slow process and we could not build up enough trains to provide a sustainable service until the evening. As a result we were forced to advise passengers to seek other forms of transport, for which we are sorry.
"Engineering staff worked through Sunday to create a new high voltage power feed into the depot. This was successful and meant Metro was able to provide passengers with a frequent service throughout today.
"We recognise that yesterday was a major failure which will have affected many passengers. We will be investigating all aspects of this incident and our response to it so that we can prevent such a failure from happening again, and we will report our findings to the North East Combined Authority."