Jennifer Lopez

Jennifer Lopez (J.Lo) is suing her ex-husband, claiming he demanded $5 million to keep him from publishing a book containing private details about the star and their relationship.

In the lawsuit filed Monday in Los Angeles Superior Court, Lopez alleged that Ojani Noa violated a confidentiality agreement by distributing the manuscript of his book to publishers, the syndicated television show "The Insider" reported. She is seeking a restraining order to keep the manuscript from becoming public.

A description of the manuscript appeared Jan. 11 in the New York Post. Lopez's lawyers contacted Noa's attorney, and Noa replied in a letter that he would continue to shop his book, the lawsuit said.

In another letter, Noa said "that he would not agree to refrain from marketing his book unless J.Lo paid him the sum of $5 million," according to the lawsuit.