A man is suing the city for $20 million over claims that he was raped by the director of an NYPD youth program as a child in the 1970s, new court papers show.

Alfredo Dones claims Gilberto Maldonado preyed on him from 1978 to 1979, while he was 13 years old and part of the Seventh Precinct’s Sea Safari Cadets, Corp, a new Manhattan Supreme Court lawsuit alleges.

The abuse included “fondling, masturbating and raping,” and first took place at the program headquarters at the Broome Street Firehouse and later during field trips to Van Cortland Park and Harriman State Park, the court papers allege.

Maldonado used “excursions outside of the headquarters” as “opportunities to assault, rape and otherwise molest” Dones, the court documents charge.

“Maldonado attacked and abused other children as well,” the suit alleges.

The NYPD and the city — which are both also named as defendants in the suit — knew or should have known about Maldonado’s “propensity to molest boys” but they “instead turned a blind eye while Gilberto Maldonado repeatedly molested Plaintiff Alfredo Dones as a child during at least a year,” the court papers allege.

“The defendants left a sexual predator in charge of a program for school-age children and took no steps to protect the young victims on whom Maldonado preyed,” the suit charges.

Maldonado could not immediately be reached for comment.

The abuse has left lasting traumatic effects on Dones, who has been forced to seek therapy.

Maldonado, “stole [Dones’] life from him … leaving him with lifelong, deep-rooted problems,” the court papers say.

Dones was able to bring his case, which would have otherwise been time barred, under the New York Child Victims Act. The CVA opened a one-year look back period for victims of childhood abuse to filed lawsuits that have passed outside of the statute of limitations.

On Wednesday, New York lawmakers extended the look back period for one more year.

The NYPD deferred comment to the city Law Department.

“These are serious allegations dating back to the late 1970s,” said a Law Department spokesman. “We will review this case carefully when we are served and respond accordingly.”

Additional reporting by Tina Moore