Dozens of subway riders were forced to exit a train and walk along the tracks Wednesday morning when the train came to a stop due to a problem that the TTC initially suspected was a partial derailment.

After further investigation, TTC workers determined part of the train did not go off the track and the issue may have been a switching problem just east of Kipling Station, said spokesman Danny Nicholson.

The mishap occurred at about 8:45 a.m.

The train was moving over switches at a slow speed when the operator felt a problem and immediately stopped. It appeared that a set of wheels known as a "truck" had started to shift between two tracks instead of staying on one track, CP24’s Cam Woolley reported.

The problem may have been caused by a buildup of ice, Woolley said.

Passenger Vincent Croos was watching a movie on his cellphone when the train came to a sudden stop.

“(The train) was going slowly and then it stopped for 10 to 15 minutes and then they started to turn it back on and then it stopped (again),” Croos told CP24. “No one was concerned. People were more worried about getting to work or school.”

After the train stopped, the power supply was turned off and passengers were helped off the train by TTC workers and police officers.

The riders were escorted back to Kipling Station, which was jammed with passengers who were delayed by signal problems that began earlier in the morning.

“We eventually just had to walk out and leave the train on the tracks," Croos said.

By 9:45 a.m., TTC workers had moved the train out of the way so they could inspect the track. Workers were seen clearing ice away from the tracks.

Train service resumed a short time later.

Wednesday's disruption added to what has been a problematic week for TTC service.

On Monday morning, subway trains bypassed Lawrence Station for about five hours because the station was flooded by a water main break.

That disruption, coupled with problems on the Bloor-Danforth line in the city's east end and streetcar delays, led TTC CEO Andy Byford to issue an apology to customers.

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