WASHINGTON – Metro is still looking for the cause of the off-hour derailment on the Red Line that disrupted service early yesterday.

Two cars of an empty six-car train on its way to the repair yard derailed near the Rhode Island Avenue station early Friday morning. The derailment damaged some signaling devices, and that disrupted Red Line service for a good part of Friday.

Metro spokeswoman Caroline Lukas says a preliminary investigation shows nothing wrong with the track or the cars. They are looking at equipment attached to the train as part of the repair work as a possible cause.

All the damage on the line has been repaired.

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