"This is until further notice. It may take a few hours or a few days, we just don't know," Christian Hoffmann, a press officer at Stockholm's public transport group, SL, said.
Traffic on the Citybanan line, which has only been open since July, was shut down at 3pm on Tuesday due to a technical problem with safety doors.
The Stockholm City and Odenplan stations are closed, and the commuter trains are instead using the old route through Karlberg and T-Centralen.
This means the commuter trains are using the same lines as intercity trains, which may cause delays and cancellations on both commuter and long-distance routes.
"On the commuter trains, we have almost 300,000 passengers per day, so it will affect many of them, and the commuter trains must run alongside regional train traffic. So it will be messy on this stretch," said Hoffmann.
Stockholm's transport commissioner, Kristoffer Tamson, argued that the Transport Administration should be better able to anticipate and fix technical problems, and should not be forced to shut down the Citybanan line on short notice for an indefinite period.
"I am really angry, and see it as my task to defend the interests of Stockholmers and commuters when such things happen," he told the TT newswire.
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