Federal prosecutors say a bureau of prisons guard is pregnant after she had an affair with a man convicted in the killing of two New York City police officers.

Nancy Gonzalez was arrested Tuesday at her home. She is charged with unlawful sexual abuse of an inmate while working at the Metropolitan Detention Center.

Authorities say the prisoner is Ronell Wilson. He was convicted in the 2006 point-blank shooting of two undercover officers. He was sentenced to death but it was overturned.

Gonzalez was expected in Brooklyn federal court later Tuesday. It wasn't clear if she had an attorney.

Federal court papers say she had an affair with Wilson for a few months before she became pregnant in June.