An official briefed on the decision says the entire Washington, D.C., subway system will shut down for at least 29 hours to inspect electrical components on the tracks.

The official spoke to The Associated Press on condition of anonymity because the official was not authorized to release the information ahead of a planned news conference at 4:30 p.m.

The official says the Metro subway system will shut down at midnight Tuesday and remain closed until at least 5 a.m. Thursday, which is the regularly scheduled opening time.

A fire on the tracks led to major delays throughout the system on Monday. The fire was caused by the same kind of electrical component that malfunctioned last year, causing a train to fill with smoke inside a downtown Washington tunnel.