WASHINGTON — The Red Line track where a train derailed Monday morning reopened Tuesday, about 28 hours after firefighters helped some 60 riders walk through the tunnel to safety.

In that time, investigators documented the scene and tracks were repaired.

Work began Monday afternoon to get the three derailed cars from the eight car train back on the tracks. The first four cars were returned to a rail yard on their own power.

By 11:40 p.m. Monday, all three derailed cars had been lifted back onto the rails, Metro’s Dan Stessel said.

The cars slid about 1,200 feet beyond the part of the rail that shattered and sent them off the tracks, but remained upright due to the walkway built into the tunnel wall. Riders and the Metro train operator did not appear to immediately realize the train had derailed, but knew there was a problem.

The train operator also had problems communicating the problems to the Rail Operations Control Center due to radio issues.

Tuesday’s repairs through rush hour:

Workers completed enough rail repairs by 3:45 a.m. Tuesday to move the three cars that had derailed along with the final car of the train coupled to them to a rail yard.

Once the cars were moved, crews worked from about 4 a.m. to just after 10 a.m. to pour concrete that then had to cure, install new rail and fasteners, then reinstall and test track circuits used to monitor train movement, among other things.

Track inspectors then eyeballed the entire stretch between Farragut North and Metro Center. Test trains ran through the area and the inbound track reopened at 10:30 a.m.

The disruption created significant delays and crowding for many Red Line riders during Monday morning’s rush hour.

Some continued service reductions are possible in the afternoon rush due to the positioning and setup of trains across the system, but Metro is expected to announce more detailed plans before the evening rush hour.