Transit passengers had to evacuate a stuck train Friday afternoon in the downtown Seattle transit tunnel.

The incident occurred southbound at 3:47 p.m. near Westlake Station, said spokesperson John Gallagher. A technical explanation of what caused the stall wasn’t immediately available.

“Passengers were offloaded, and we’re now single-tracking on the northbound tracks,” Gallagher said at 4:18 p.m. Rider alerts from the agency mentioned both a blockage and mechanical problems.

The stall caused delays in and around the downtown corridor, where the 1 Line travels between Northgate and Angle Lake.

The train was cleared just before 5 p.m., according to Sound Transit.

Sound Transit recently rewired the tunnel’s power supply lines to make it easier for trains to detour around each other, in a program called Future Ready. It’s unclear whether the upgrade played any role in Friday’s event.

In 2021, a stall forced hundreds of football fans to self-evacuate after the Apple Cup football game in late November. The northbound train’s electrical wires were severed by protruding metal rods between the rails, causing a sudden blackout and power loss in the train.