Passengers on two trains were stuck between stations after a tech issue on the Tyne and Wear Metro.
Most of the service was brought to a standstill between about 15:45 GMT and 16:15 GMT on Thursday, Metro operator Nexus said.
Nexus said the problems, initially thought to be a power outage, were caused by an IT system issue which was still being investigated.
All trains resumed running on Thursday evening, with delays to most services.
One train was stuck between Heworth and Pelaw and the other between Byker and Chillingham Road.
Nexus said the stranded trains were back running before its teams were on site to help passengers.
During the outage, Nexus was still able to run a shuttle service between Brockley Whins and South Hylton on Network Rail infrastructure.