Train operator SMRT has withdrawn the train in Friday night's incident from service so that it can check its doors more thoroughly.
An object had jammed a door, causing the train to stall briefly at Redhill MRT station at 11.06pm because the doors would not close. Passengers travelling in the direction of Joo Koon on the East-West Line were told to disembark and wait for the next train at the platform, which came shortly and departed at 11.14pm. Service was not disrupted, said SMRT.
The operator said the object could have been dislodged while the train was making its way back to the depot, as the door was able to close when engineers inspected it at the depot.
"As such, there is no way of knowing what that object precisely is," said a spokesman. As a safety measure, it has withdrawn the train from service for a more thorough inspection.