WASHINGTON — A Metro machine derailed in the first 24/7 surge zone early Tuesday, and a part may have made contact with a passing Silver Line train that was just wrapping up Monday night service.

The Silver Line train was passing through the single-tracking zone between Ballston and East Falls Church around 12:05 a.m.  when a “spiker” — a 21-by-10-foot machine that rides the rails and drives spikes into wooden rail ties to keep the track stable — derailed, Metro said in a statement.

The train operator reported that the train may have hit the spiker’s mirror, but the train was cleared to continue on to East Falls Church after an inspection. Riders on the train got off there and were put on a different train to complete the trip to Tysons or Wiehle-Reston East.

“Employees directly involved” in the incident “have been temporarily removed from service during the investigation,” Metro said.

Metro suspended overnight work in the 24/7 work zone for a safety review, but Metro’s Richard Jordan said it is not expected to delay the end of the work zone Thursday night.

Single tracking continued as originally planned Tuesday morning.