A CSX Corp. freight train plowed into construction equipment left on the railroad's track parallel to the Metro track in Silver Spring Thursday night, damaging about 250 feet of Metro's chain-link fencing, officials said yesterday.

No one was injured in the incident, which occurred just north of the Silver Spring station and within five miles of the sites of two recent CSX train derailments that disrupted Metro's Red Line service.

The 90-car train hit a backhoe, a machine used for digging ditches, about 10:47 p.m., damaging the fence and triggering a warning device, said CSX spokesman Lloyd Lewis.

The Metro track at that location leads from the Silver Spring station to a storage yard and is not used for passenger service, said Metro spokeswoman Beverly Silverberg.

The backhoe apparently was left on the track by vandals who had moved it from a nearby work site, Lewis said.

CSX freight trains derailed Sept. 5 and June 19, tearing up hundreds of feet of parallel Metro track, cutting off Red Line service for at least three days each time.

After the most recent derailment, CSX agreed to limit its trains to 30 miles an hour along the corridor shared with Metro for 90 days, while the two organizations conduct a joint safety study.