A Bronx woman was killed when a U.S. Postal Service mail truck struck her while she laid down in the middle of a Brooklyn roadway early Tuesday morning, authorities said.

Dorria Campfield, 52, was near the intersection of Fulton Avenue and Rockaway Avenue in Brownsville at about 5 a.m. when the eastbound truck hit her, cops said.

She was rushed to Interfaith Hospital where she was pronounced dead.

The 66-year-old U.S. Postal worker remained at the scene, cops said.

It remains unclear why the woman was laying down in the street.