- Washington Mayor Muriel Bowser said she learned of the shutdown late Tuesday afternoon
- Metro riders react to shutdown with a mixture of humor and trepidation
- Metrorail system will shut down for safety inspections until 6 a.m. Thursday
- The closure comes after an electrical fire in a Metro tunnel on Monday
(CNN)The entire Metrorail system in the nation's capital will be shut down until Thursday morning for safety inspections of hundreds of electrical cables, officials said Tuesday.