Hong Kong's leader said on Tuesday the government would not rush to introduce a new signal system on the city's subway until it was proved to be safe, after a trial run ended in a crash which derailed a carriage, injured a driver and shut down a key link on the network.
Chief Executive Carrie Lam Cheng Yuet-ngor said officials would be similarly cautious with the scandal-plagued Sha Tin-Central link, the next new line set to open on the MTR, which will use a similar system.
City commuters looked set for an extended period of disruption. Officials admitted the challenge of clearing the wreckage from Monday's crash - which happened with no passengers on board - meant they could not say when services would get back to normal.
Trains between Central and Admiralty stations on the Tsuen Wan line were suspended. Other MTR lines, and the rest of the Tsuen Wan line, were running as normal.