Northbound trains on Metro-North's Danbury Branch became delayed at about 2:30 p.m. Wednesday due to mechanical difficulties.
At 3 p.m., Metro-North said the delays were up to 50 minutes on the branch, which runs between Norwalk and Danbury.
Train riders are urged to listen for announcements at their stations. It was not clear when the train service would be back on schedule.
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