ARLINGTON, Va. -- A signaling problem is causing delays throughout the Metro system Monday night, Metro officials said.

Metro officials said one of Dominion Virginia Power's electrical feeders went down near the Vienna station on Friday. The West Falls Church, Dunn Loring and Vienna stations have experienced problems with insufficient power since then. Metro has been using power from its West Falls Church railyard to help keep trains running.

Dominion expects the problem to be fixed by 1 a.m. Tuesday, in time to avoid delays during the morning's rush hour.

Meanwhile, Vienna-bound Orange Line trains will run 12 minutes apart between the West Falls Church-VT/UVA and Vienna/Fairfax-GMU stations, and every other train will terminate at West Falls Church, Metro said.

The Dunn Loring station is without power, and elevators and escalators at the station are not working. Metro said it is trying to use generators to restore power there.

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