Authorities are looking for a gray SUV that may be connected to a pedestrian hit-and-run in East Harlem.

Christopher Costa, 36, was pronounced dead at Mt. Sinai Hospital, where he was taken after being struck by a driver near the corner of Madison Avenue and East 115th Street shortly before 10 p.m. on Tuesday, police reported.

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“He was face up, but his skull was open. The cars didn’t stop. They just kept driving around him,” witness Vivian Rolon said to the New York Daily News. “A lady who got out was standing over him, feeling his neck. He still had a pulse. It was terrible, a nightmare. I don't think I'll be able to sleep after this.”

A preliminary investigation determined that a gray SUV heading north on Madison Avenue struck Costa, according to police, who added that the driver fled the scene.

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No arrests have been made, and the investigation is ongoing, police added.