More than 725,000 Metro rides are taken every day, but not one train carried passengers Wednesday while crews checked approximately 600 underground jumper cables, WRC reported.

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The decision was made late Tuesday afternoon surprised riders who depend on the subway to get around the nation's capital, The Washington Post reported.

By late Wednesday morning, half of the cables, which are part of the system's third rail that provides power to the trains, had been checked. Some had to be replaced.

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Some commuters were trying to decipher bus routes and schedules, and others took to the roads and drove to work.

To help lessen the impact, the federal government's Office of Personnel Management announced that it was staying open, but workers were able to telework or take unscheduled leave.

The cables were inspected after a fire Monday at the McPherson Square station, The Washington Post reported.

The same problem happened in January 2015 at L'Enfant Plaza. A train filled with smoke when it was stopped in a tunnel near that station. A woman died and dozens were injured.

The Metro has never been shut down completely other than for weather since it started in 1976.

The system consists of six lines and 91 stations, according to Metro's website.

The work is scheduled to be complete by the time Thursday's commute begins at 5 a.m.