Update, 3:40 p.m.: Metro said this afternoon that crews had made a temporary fix to the cracked rail on the Blue/Orange line near the Rosslyn station.

The fix involved installing a “splice bar,” something similar to putting a cast over a broken arm, explained Dan Stessel, Metro’s chief spokesman.

“It holds the two pieces of rail together so trains can operate safely,” Stessel said.

Crews will work overnight, he said, to replace a 40-foot section of track with new rail.

Update: Metro said trains were resuming normal operations as of 12:20 p.m. Officials said in a statement that crews made “temporary repairs to allow trains to operate over the affected section. Permanent repairs will be made tonight after system closing.”

Original post: Metro said crews are working to fix a cracked rail this morning at the Rosslyn station.

The crack was discovered around 10:45 a.m. when a “signal system showed false occupancy,” according to Metro spokesman Dan Stessel.

He said a false occupancy signal causes a “break in the electrical current” and can show a train is there even when it is not.

He said crews were inspecting the area now and trains are single tracking on the Orange Line between Ballston and Foggy Bottom and on the Blue Line between Arlington Cemetery and Foggy Bottom.

Passengers can expect delays of between 10 and 15 minutes, Stessel said.

Last week, a cracked rail delayed riders on the Red Line. In early January, sub-zero temperatures caused cracked rails on the Yellow and Red lines.

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