A pregnant prison guard has been arrested for allegedly having sex with a convicted cop killer serving time for gunning down two NYPD detectives on Staten Island in 2003, sources familiar with the investigation tell NBC 4 New York.

The 29-year-old Bureau of Prisons employee, Nancy Gonzalez, was arrested Tuesday at her home on Long Island. Sources also tell NBC 4 New York that both Gonzalez and the inmate, Ronell Wilson, have made statements to investigators saying that the baby is his child.

Gonzalez is eight months pregnant. The charge is unlawful sexual abuse on a ward; her lawyer said outside court that she was upset and needed to get home because she was trying to focus on having a safe pregnancy.

Wilson was convicted in 2006 of shooting detectives James Nemorin and Rodney Andrews in the back of their heads in a car March 10, 2003 on Hannah Street in Staten Island. 

Court papers say that in a recorded call to another inmate at the federal prison in Brooklyn in December, Gonzalez allegedly said, "I took a chance because I was so vulnerable and wanted to be loved and now I am carrying his child." 

Gonzalez allegedly said during that same conversation that she "kind of got sucked into his world" and that she "felt like, well, why not give him a child as far as giving him some kind of hope."

Authorities say the romantic relationship went on from March to August of last year, and that she is seen on video in the federal prison spending several minutes at a time with the inmate in a vacant activity room.

Court papers also say she is seen on video standing at his cell door for "lengthy periods of time while the other inmates are locked into their cells at night."

During another recorded conversation with the other inmate, Gonzalez allegedly said she "just basically got wrapped up in something that I should not have got wrapped up," and described Wilson as an inmate so high-profile that "when he farts it makes the news."

She also allegedly expressed fears about what she would say to her future child about how he was conceived. 

"I know what is going to be said about me," she said. "I know that for me as a parent, how am I going to explain this to this little boy? ... Mommy got wrapped up ... And then the opposite end is with a person who took lives. So how do you explain that?"

Investigators first learned of the alleged relationship from other inmates, who told them they could see Gonzalez and the inmate "hugging and kissing" in the activity room.

Another inmate reported that he also saw Gonzalez's inmate standing at his cell, with the door propped open, exposing his genitals as Gonzalez left the cell, court papers say.

After receiving the tips from the inmates, investigators began reviewing video of Gonzalez at work.

Investigators say the relationship between Gonzalez and Wilson ended in August, and that she became involved with another inmate in September, telling him in recorded phone calls the details of how she became pregnant by Wilson.

Wilson was sentenced to death in the killing of the two police officers, but the sentence was thrown out in 2010 by an appeals court.

A new jury must decide his fate. But the trial's penalty phase has been put off as Wilson's lawyers seek to convince a judge that he's ineligible for the death penalty because he's mentally disabled.