MARC riders face 25-minute delays after Rockville derailment

A CSX train derailed in Rockville, Md., around 12:25 p.m. Monday, delaying MARC Brunswick Line trains between Kensington and Rockville by about 15 to 25 minutes, Montgomery County fire officials said in social media posts.

The disruption matters for Montgomery County residents and DC commuters because the Brunswick Line connects Maryland suburbs with Union Station, while officials reported no disruption to Metro Red Line or Amtrak service.

Two distributed power units and an auto rack car came off the tracks near East Middle Lane and Hungerford Drive, officials said. A distributed power unit is a locomotive unit positioned within a freight train to help move and control it; an auto rack car is used to transport vehicles.

One train car fell over, but officials said no one was aboard and no injuries or spills were reported. Montgomery County fire and police officials responded to the scene near the Montgomery College-Rockville campus, close to Mannakee Street.

Pete Piringer, a spokesperson for Montgomery County Fire and Rescue Service, said on X that a single CSX train car had slipped off the railroad track and was on its side, with “no fire, no injury.” He later said train traffic was blocked or stopped in Rockville.

The incident affected a busy shared rail corridor used by freight and commuter service in Montgomery County. Officials said track one remained clear, limiting the reported impact beyond the immediate area, though MARC riders on the Brunswick Line still faced delays through the affected stretch.

For riders, the practical effect was concentrated on MARC’s Brunswick Line rather than the full regional rail system. The reported delay window applied to CSX Brunswick Line trains between Kensington and Rockville, a segment used by commuters moving between Montgomery County and DC.

The location also matters locally because the derailment occurred near Montgomery College’s Rockville campus and close to roads used by residents, students and commuters. Emergency personnel were sent to assess the rail scene and secure the area.

| Figure | Detail |

| 12:25 p.m. Monday | Reported time of the derailment |

| 15 to 25 minutes | Expected delay for affected Brunswick Line trains |

| Two | Distributed power units that derailed |

| One | Auto rack car that derailed |

| Track one | Reported clear after the derailment |

WMATA Red Line trains between Rockville and Shady Grove were not affected, officials said. Amtrak service also had no reported disruption, leaving Metro as an option for some riders traveling between upper Montgomery County and DC.

The cause of the derailment is under investigation. Officials had not reported injuries, fire or spills, and emergency crews remained focused on securing the scene and the tracks.

Source: Montgomery County Fire and Rescue Service social media posts and Montgomery County officials, Oct. 12, 2026