A computer problem caused major delays in SkyTrain service between Nanaimo and Columbia stations Saturday, as many frustrated riders took to social media to vent about being stuck in the sweltering heat.

According to TransLink, the Expo and Millennium lines were shut down between the two stations because of a computer card communication problem. The issue also caused delays between Broadway and Nanaimo stations.

Many passengers took to Twitter to express their anger, with some saying they were stuck inside of hot cars on one of the hottest days of the year. Temperatures were expected to push 32 degrees in inland Metro Vancouver Saturday, according to Environment Canada.

A spokesperson for TransLink confirmed some of the earlier model trains do not have air conditioning, but are equipped with heavy duty fans. No medical emergencies were reported during the delays.

The trains that were delayed the longest were immobile for 22 minutes, TransLink said, but those were air conditioned cars.

TransLink tweeted at 3:59 p.m. that trains were once again running system-wide.