Democrat gubernatorial candidate Phil Murphy is criticizing Republican opponent Lt. Gov Kim Guadagno over a new campaign ad about illegal immigration.

The commercial features Murphy saying he would have "the back" of illegal immigrants. 

In the commercial, a male narrator says, "Illegal alien and child rapist Jose Carranza shot four New Jersey students in the head. Three died, shattering their families.” It is referencing the 2007 Newark schoolyard murders.

The narration continues, "When asked about deporting criminal illegals, Phil Murphy said..." The ad then shows Murphy saying, "My bias is going to be having their back."

The ad also references Murphy’s statement during Tuesday night’s debate that he would make New Jersey a “sanctuary state” for undocumented immigrants.

The commercial does leave out Murphy’s comments during the debate that the 2007 crimes were "heinous" and that those responsible should be prosecuted "to the fullest extent of the law."

Murphy released a statement Wednesday when the commercial was released, which said in part, “This ad, which represents politics at its worst, is vile and deceitful. She took an answer I gave about standing up for immigrant communities and knowingly distorted it.

The statement continued, "Kim Guadagno should be ashamed of herself for the way she's politicizing the deaths of three children and painting a community with the broad brush of a murderer, a tactic she must have gleaned from President Trump.”

Former Vice President Joe Biden also spoke out against the ad during a Murphy campaign event Thursday.  

Biden said it was "the return of Willie Horton,” referring to an explosive 1988 anti-Michael Dukakis ad featuring a black felon. The ad was designed to play on fears of Democrats' supposedly soft-on-crime policies. They were also condemned as racist.

Six men and boys were convicted or pleaded guilty in the 2007 Newark slayings. Carranza got a total sentence of 155 years and an appeal earlier this year was denied.