An off-duty NYPD detective was brutally stabbed and slashed during a brazen robbery in the Bronx Friday afternoon, law enforcement sources said.

The detective was ambushed when the e-bike-riding duo approached him around 1:40 p.m. at East 206th Street and Rochambeau Avenue in Norwood, the sources said.

He was knifed in his neck and the leg, and rushed to Jacobi Medical Center, where he is expected to survive, according to sources and the FDNY.

Two male suspects, believed to be Hispanic, quickly took off on their e-bikes, the sources said.

It was not immediately clear what, if anything, was stolen, according to the sources.

The detective — assigned to the 44th Precinct — joined the NYPD in July 2016, the sources said.