Bestselling author Peter Maas, whose books on crime became such films as “Serpico” and “The Valachi Papers,” died Aug. 23 at Mt. Sinai Hospital in New York City of an undisclosed cause. He was 72.

During his prolific 50-year career, Maas detailed the life of incorruptible NYC policeman Frank Serpico. That book became the movie “Serpico” and won Al Pacino an Oscar nom for his portrayal of the man; book also spawned a short-lived TV series. Mass split the screen rights on the book with Serpico.

His 1969 book “The Valachi Papers,” about mobster Joe Valachi and his decision to become a federal informant, was an international best seller and hit movie.

Maas also collaborated with Gambino family underboss Sammy “the Bull” Gravano, whose testimony landed mobster John Gotti behind bars for life. The “Underboss” book became a New York Times No. 1 bestseller.

Maas’ other books includes “The King of Gypsies,” “Made in America” and “Marie: A True Story,” which became a movie with Sissy Spacek.

“The Terrible Hours,” his account of the first successful submarine rescue, was a Times best seller last year.

In all, Maas wrote more than a dozen novels and nonfiction books as well as numerous investigative pieces.

The native New Yorker began writing while attending Duke U. He moved on to the New York Herald Tribune in Paris before joining Collier’s in 1955. While at Look magazine, he drew national attention for his story of a Louisiana black man who had been on Death Row longer than any other prisoner in the United States. His work also appeared in New York magazine and the Saturday Evening Post.

Maas is survived by his third wife, Suzanne Maas, and two sons.