A man was struck and killed by a subway train on the Upper East Side Tuesday morning.

Around 4:30 a.m., a northbound subway train struck the victim near the 77th Street station, officials said to NBC4.

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The subway, an uptown work train, was unable to stop before hitting the man, who had been seen by the motorman on the roadbed, sources said to the New York Daily News.

Authorities told NBC4 they believe the victim may have been walking on the tracks, NBC4 added.

The victim died at the scene, and his name has not been released, according to the Daily News.

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An investigation into the incident was ongoing Tuesday morning, NBC4 stated.