The off-duty officer was punched and kicked at West 125th Street and Lenox Avenue, police said. View Full Caption DNAinfo/Gustavo Solis

MANHATTAN — Police were questioning a man after an off-duty NYPD sergeant was beaten, kicked and her face cut in Harlem Wednesday morning, officials said.

The 43-year-old sergeant, whose name was not released, had just left Dunkin' Donuts at West 125th Street and Lenox Avenue about 6:45 a.m. when a man, who appeared to be homeless and had been acting erratically moments before, pounced on her, sources said.

He punched and kicked the 19-year police vet, who currently patrols public housing, knocking her to the ground and leaving her with a cut above her left eye and a bruise to the back of her head, sources said.

She was in stable condition and received several stitches for her injuries at an area hospital, police said.

The attacker fled north on Lenox Avenue. A man was arrested later Wednesday and had not been formally charged as of noon, NYPD officials said.

Investigators were still trying to figure out why the man attacked the officer, police said.

The Wednesday attack comes a month after two detectives were gunned down in Bedford-Stuyvesant.