The suspect in a brutal sex assault on a New York City mother that led to the creation of a 40-member task force was arrested Tuesday at a South Carolina motel, NYPD officials announced.

Ronald Williams, 21, was arrested in the “violent, random” sexual assault on a 52-year-old woman just after she dropped off her son at school.

The April 30 attack left the victim unconscious in a basement stairwell, where police officers found her with trauma to her face and body, according to officials.

“It was unusually brutal -- she was physically assaulted, very badly,” Capt. Elisa Anders, of the NYPD’s Special Victims Unit, told WABC-TV of the crime. “She’s still hospitalized.”

A 40-member special task force assigned to the case was utilizing technical and social resources in the search for Williams, according to the station.

“A case like this, leaving a victim as brutally beaten as she was is extremely troublesome,” Anders said.

Williams was extradited to New York from Columbia, S.C., on a probation violation.

A $10,000 reward had been offered for information leading to an arrest in the case.