Train riders between Rye and Old Greenwich may experience delays of 15 to 20 minutes and possibly up to 40 minutes due to limited track availability, said Metro-North spokeswoman Nancy Gamerman.
At about noon, a piece of track equipment — knowns as the TX3003 or a tie inserter — derailed between Cos Cob and Greenwich, she said.
A Metro-North employee sustained a minor injury in the incident, she said.
One track is out of service, with single track service through that area delaying trains, she said.
Metro-North expects to have the track fully back in service by 3 p.m. Thursday, she said.
There was no information available on how the incident occurred.
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