A janitor was arrested for allegedly locking a 17-year-old girl inside of a school office in Brooklyn and raping her, police sources said.

Hernan Zapata, 51, was working at the Fort Greene middle school where the young woman was visiting at around 3:30 p.m. Saturday, sources said.

Zapata then allegedly grabbed her and locked her inside an office, where he assaulted and raped her, sources added.

Zapata was charged with rape, criminal sexual act, sex abuse, sexual misconduct, unlawful imprisonment and assault, police said.

He has no prior arrests in New York City, law enforcement sources said.