Wellington trains are running again following a 55-minute suspension due to a signals failure this afternoon, but more delays are expected.
Commuters were stranded during rush hour as all trains in and out of Wellington, except the Johnsonville line, were stopped at 4.35pm.
KiwiRail North Island passenger services manager David Knight said the suspension was due to a fault in the integrated signals and points control system.
"We can't operate points of signals normally, so temporarily stopped train services into and out of Wellington station while we dealt with the issue," he said.
"We are running trains on all lines again but there will be some disruption to services as the underlying computer fault is not yet fixed."
Mr Knight said due to the short notice and the number of people waiting to board trains, bus replacements have not been arranged.
"While staff continue to fix the issue, we are running trains, although not yet with the usual speed or frequency. We will keep our passengers up to date with station announcements.
"We apologise to our passengers for the delay to the journey and will get them home as soon as we can."
Commuters expressed their frustration on Twitter, with one calling Tranz Metro a "useless third world rail system" and another asking "who the hell did the work on the new lines?".
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