For the second time in a week, the doors of a busy TTC subway train opened while inside a tunnel, away from the platform.

In both cases, the train was not moving but the incidences caused significant delays.

This morning, the subway was delayed for nine minutes after the doors opened prematurely before pulling out on the southbound tracks at King Station.

The train left the station and headed towards Union Station when a red light signalled it to stop.

“There was a trainee guard and for reasons we are trying to understand, the guard opened the doors,” said Brad Ross, spokesperson for the TTC.

The power was immediately cut and the track levels were checked before power was restored nine minutes later.

The train was taken out of service after it pulled into Union Station.

Ross said the doors opened because of “human error” and that officials are looking at ways to prevent similar incidents from happening in the future and strengthen the safety protocol.

TTC officals had already profusely apologized for a series of problems on the subway line Monday.

One of the major problems that evening was when the doors of a stationary train opened while in the tunnel approaching Dupont Station.

No one was injured but commuters were delayed for nearly 25 minutes.

At the time, Ross told CP24 “crew error” was to blame for the incident.

TTC CEO Andy Byford put up a video on YouTube the next day officially apologizing for the event.

“Two weeks ago I launched the inaugural TTC Customer Charter, in which we made 31 commitments to improving service and the key to that is increased reliability and punctuality of service. Clearly we didn’t meet that objective last night,” he said in the video. “I’m sorry for the delays and appreciate that it was a frustrating ride home.”

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