[1] At approximately 4:57 pm EDT (20:57 UTC) on Monday, June 22, 2009, Washington Metro Train 112, bound from Glenmont to Shady Grove, left the Takoma station.

[1] A series of near-collisions in 2005 in similar circumstances in the tunnel between Foggy Bottom and Rosslyn stations led to a new test procedure that would have identified the faulty circuit after installation.

[4] Survivors described the crash as "like... hit[ting] a concrete wall," with air clouded by smoke and debris, and panic among passengers when car doors did not immediately open.

Oglesby and Martin gave first aid to the more seriously injured victims until help arrived, and informed responding emergency personnel that the rails were still powered and needed to be shut down.

[16] Rescuers worked through the night of June 22, using cranes and heavy rescue equipment to free trapped passengers and search for bodies.

[7][17] Fire Chief Dennis Rubin initially confirmed four fatalities (including the train operator) and 74 injuries, 14 of which were considered moderate and 6 critical.

[18] Five of the dead were discovered in the wreckage and removed from the site of the collision on the morning of June 23, as cranes dismantling the wrecked trains revealed the bodies.

David F. Wherley Jr. of the District of Columbia Air National Guard – known for deploying fighter jets to defend Washington, D.C. during the September 11 attacks – died in the collision along with his wife, Ann; the other passengers who died in the crash were Lavonda King, Veronica DuBose, Cameron Williams, Dennis Hawkins, Mary Doolittle, and Ana Fernandez.

[21][22] According to Daniel Kaniewski, a former George W. Bush administration Homeland Security official now with the Homeland Security Policy Institute at George Washington University, the overall emergency response was "calm and ordered," indicating that U.S. emergency response "during extraordinary incidents [has] significantly improved" since the September 11 attacks.

[23] Immediately following the incident, Red Line services were suspended between the Fort Totten and Takoma stations, and New Hampshire Avenue was closed.

[24] Service between the Silver Spring and Rhode Island Ave–Brentwood stations was suspended pending the completion of the initial investigation and the clearing of debris.

Washington Mayor Adrian Fenty said that transportation "all along the East Coast will be significantly impacted,"[17] as Amtrak and MARC Trains run on tracks adjacent to the crash site.

[25][26] The Red Line was projected to be very crowded after resumption of service and the Washington Metropolitan Area Transit Authority (WMATA) advised people to take alternate bus routes.

[5] The 1000-Series entered service in 1976 when the Metro system opened, and were refurbished and had their motors converted from DC to AC propulsion by Breda Costruzioni Ferroviarie in the mid-1990s.

In 2006, the NTSB cited the 1000-Series cars as "vulnerable to catastrophic telescoping damage and complete loss of occupant survival space in a longitudinal end-structure collision".

[37] On June 24, WMATA issued a press release stating that the agency is "not likely to know the cause for several weeks or months as the investigation unfolds.

[citation needed] On June 22, 2015, the sixth anniversary of the crash, the Legacy Memorial Park in honor of the victims was opened;[47][48] ground was broken exactly one year previously by Mayor Vincent C.

[51] The same week as the memorial dedication, the National Transportation Safety Board held hearings related to another fatal incident in the Metro system that happened earlier in 2015; the juxtaposition of the two events was noted by some commentators.

[50][52] On the third anniversary of the crash, NTSB chairwoman Deborah Hersman and Mayor Gray attended the unveiling of a plaque on the Charles A. Langley Bridge.