An off-duty corrections officer fatally shot his girlfriend in the Bronx late Wednesday, law enforcement sources said.

The 35-year-old woman was struck once in the chest at about 10:38 p.m. in the Highbridge neighborhood before she was rushed to Bronx-Lebanon Hospital Center, where she died, officials said.

A law enforcement source revealed that the shooter was an off-duty corrections officer, while the NYPD would only say a suspect was being questioned.