A southbound 6 subway train struck a piece of metal, causing an electrical fire Monday morning in Manhattan.

It happened around 9:39 a.m. near the 68th Street and Lexington Avenue stop on the Upper East Side, the Metropolitan Transportation Authority said. 

A rescue train was brought in to move passengers to the 59th Street and Lexington Avenue stop. The passengers had been stuck on the train for nearly an hour before they were successfully removed at around 10:30 a.m., the MTA said. 

Video from the scene showed the 6 train halted at the entrance of the station, with MTA workers nearby. 

6 trains were running express in both directions from Grand Central to 125th Street. Downtown 5 trains were running via the 2 line from 149th Street-Grand Concourse to Nevins Street. There were delays on the 2 and 4 lines while they share tracks with the rerouted trains. 

Subway passengers who spoke with CBS News New York said they were frustrated by the delays. Downtown service has since been restored on the 4, 5 and 6 lines. 

The MTA did not say where the large metal object came from or how it ended up on the tracks. 

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