Metro: 'Foreign Object' Caused Smoke at Friendship Heights Station

Metro and the Federal Transit Administration are focusing on a "foreign object" as the possible cause of a recent scary smoke incident at the Friendship Heights Station on the red line that resulted in an evacuation of the train.

While the investigation is ongoing and Metro hasn't yet determined the cause of the April 23 incident, which forced the train's operator to back up to the Tenleytown station to get passengers off, "the investigation is focusing on a foreign object, specifically a metal part of a railcar, becoming dislodged and making contact with the electrified third rail," Metro said April 25 in its preliminary findings.

When the object came into contact with the third rail, it appears to have caused "a loud noise, flash and smoke," the statement reads. In fact, the operator of the red line train reported hearing "a loud boom and smoke entering the lead car."

The eight-car train stopped in the tunnel before reaching Friendship heights. Passengers were sent to the back of the train, and then the operator reversed direction back to Tenleytown so passengers could offload in what was a chaotic situation.

"Prior to the train being moved, an unknown passenger pulled an emergency door release, causing the train to lose 'all doors closed' indication," the statement reads. "It was confirmed that no passengers 'self-evacuated' from the train. Once all doors were confirmed closed, the train was moved."

Authorities said there were no injuries. Investigators have completed inspections on all power infrastructure in the tunnel. The investigation into the cause continues.

The incident is similar to a smoking incident at L'Enfant Plaza last year that resulted in the death of a woman. Another smoking incident last month prompted Metro to shut down the entire system for a day to get a handle on the problem.