Publisher Signet Books and romance writer Cassie Edwards are divorcing after allegations emerged earlier this year that the author lifted passages in many of her books from other sources.

"Signet has conducted an extensive review of all its Cassie Edwards novels, and due to irreconcilable editorial differences, Ms. Edwards and Signet have mutually agreed to part ways," said Signet, a branch of the Penguin Group, in a statement Friday.

Edwards, whose 100 books include Bold Wolf, Silver Feather, Shadow Bear and Falcon Moon, did not release any comment about the situation. The author made a name for herself by focusing on stories about native peoples.

In January, a romance novel website, smartbitchestrashybooks.com, posted excerpts from the Illinois-based writer's works next to similar passages from reference books and magazines.

At first, Penguin said Edwards had "done nothing wrong" and that any use of other texts was protected by "fair-use doctrine."

In a January interview, Edwards admitted that she "takes" material from other works, but said she didn't know she was supposed to credit her sources.

Edwards, who began penning romances in 1982, has won the Romantic Times Lifetime Achievement Award and the Romantic Times Reviewer's Choice Award.

Prolific romance writer Nora Roberts blasted Edwards for her methods.

"By my definition, copying another's work and passing it as your own equals plagiarism," Roberts said.