McMillan was one of nine people killed when her train, under automatic computer control, apparently failed to register a signal and avoid a collision with a train that had stopped near a curve between two stations.

CNN: Metro driver called a hero who saved lives in crash

The rear train was operating on "automatic" mode, which is routine during rush hour, and preliminary evidence shows that the driver may have employed the brakes, Hersman said.

CNN: Investigator: D.C. Metro crash 'a scene of real devastation'

Announcements by on-board train staff "were not that bad" and it was automatic ones which were most annoying, the Lib Dem MP suggested.

BBC: Train operators urged to curb 'excessive' announcements