12/20/2011 10:21 am ET Updated Dec 20, 2011

Orange, Blue Line Service Restored Through L'Enfant Plaza After 'Track Obstruction' (UPDATES)

WASHINGTON -- Rail service on Metro's Orange and Blue lines through L'Enfant Plaza was suspended due to a "track obstruction" after a piece of a Blue Line train fell off and hit the third rail on Tuesday morning.

The closure, which lasted into the afternoon, caused major delays along the Orange and Blue lines through downtown, with no train service service between the Federal Center SW and Metro Center stations.

Metro re-established service on one track through the affected area by 12:55 p.m. Full service was restored after 2 p.m.

Metro confirmed Tuesday morning that the situation did not involve a derailment and that there were no injuries. There were earlier reports that all of the passengers were evacuated from trains impacted, but the fire union tweeted around 11:45 a.m. that there were still "1&1/2 cars left to evacuate" adjacent to the Smithsonian station.

As the situation developed Tuesday morning, Metro reported that a piece of the train had fallen off, but it was not immediately clear exactly what had hit the third rail, which powers the train.

According to NBC Washington:

The piece was not a wheel, [Metro spokesman Dan] Stessel said, but the piece that fell came in contact with the third rail, which caused sparking and smoke in the tunnel.

There was there was initial speculation that a wheel had fallen off a train. Also, there was discussion that a train axle was to blame.

According to WTOP, officials said a "friction ring," part of a braking system, fell of the train when it hit the third rail.

The situation caused mass confusion as riders on affected trains were evacuated and others delayed tried to get from Point A to Point B. According to WTOP:

One woman says she immediately thought about Sept. 11 when she heard a loud bang while riding the train. She surfaced from Smithsonian Metro station in tears to greet her husband with a hug and kiss.

As Dr. Gridlock observed at Metro Center, where Orange and Blue line trains temporarily terminated, "I saw or heard just about every communications problem that riders complain about during rail emergencies." This included platform personnel who "did'’t know where the arriving trains would be going ... electronic display signs [that] were next to useless" in addition to infrequent and complicated announcements.

Around 11:43 a.m., D.C. Fire and Emergency Services officials told WTOP that it was assisting approximately 300 people.

Limited bus service was established following the incident and Metro suggested that riders on the Green and Yellow lines looking to transfer to the Orange and Blue Line service to points downtown and in Virginia via Rosslyn should do so via Gallery Place and Metro Center.

Track inspections were underway by 12:23 p.m., which Metro reported was the final step before re-energizing the third rail. At 12:55 p.m., Metro reported it had restored service to one track through the affected area. Full service was restored after 2 p.m.

At a Tuesday afternoon press conference, Metro officials said that the friction ring in question fell off of a Blue Line train and "impacted" two Orange Line trains, according to The Washington Post's Dana Hedgpeth. Metro General Manager Richard Sarles said that the entire 5000-series rail fleet would be inspected.

Earlier during the Tuesday morning commute, an unauthorized man was found walking on Red Line tracks near the Judiciary Square station, which caused delays.

This story is developing and was last updated at 4:30 p.m. ...