Authorities charged a man and woman with murder Thursday in the slaying of a North Jersey tourist who was abducted in Atlantic City on May 21.

Craig Arno, 44, and Jessica Kisby, 24, pleaded not guilty Wednesday to kidnapping and carjacking charges in the abduction of Martin Caballero, 47.

Officials upgraded the charges after confirming that a body found Sunday on a farm west of Atlantic City was that of Caballero, the grocer from North Bergen kidnapped in a parking garage at the Trump Taj Mahal Casino Resort.

Caballero died from multiple stab wounds to the chest, authorities said Thursday.

He was identified through DNA records from his time in the military.

"I can say confidently that this offense as alleged was random in nature," Atlantic County Prosecutor Theodore Housel said. "This crime is not indicative of a pattern of crime in Atlantic City."

He called the killing "once in a generation, once in a decade."

Caballero didn't know Arno or Kisby, Housel said.

Caballero traveled to the casino-hotel with his family to celebrate his daughter Jessica's 22d birthday. He dropped his wife off in front of the casino and drove into the garage. At that point, around 10:30 p.m., he was abducted, police said.

More than two hours later, his ATM card was used to make a maximum $300 withdrawal from a Bank of America machine in Egg Harbor Township.

Records show the card was also used to buy a fire starter and five gallons of gasoline in a container, authorities said.

Shortly after, Caballero's luxury Lincoln was found torched about 50 miles away, in a parking lot, close to woods in Gloucester Township.

On Thursday, Gloucester Township authorities charged Arno and Kisby with arson and hindering apprehension for setting fire to Caballero's car.

Bail was set at $75,000 on the Gloucester Township charges.

On Thursday, Kisby, an Egg Harbor Township mother of a 5-year-old, was charged with armed robbery and weapons charges in connection with a robbery of a Pleasantville Kmart on May 24. Arno, a career criminal from Atlantic City, had already pleaded not guilty to armed robbery, assault, and weapons offenses in the Kmart robbery.

The two remained in the Atlantic County Jail on $2 million bail apiece.

Arno's criminal record dates to 1981, when he was arrested for a City Avenue drag-racing accident that killed Karen McNaughton, 27, a nurse on her way to work. Arno was originally charged with murder after authorities said he had crashed head-on into McNaughton's car while racing as fast as 80 m.p.h. But the charge was reduced to manslaughter, and he was sentenced to five years' probation.

Over the next 20 years, he was in and out of jail as an adult on charges of bank fraud, credit-card fraud, counterfeiting, and parole violation in Philadelphia, New Jersey, and Texas.

Court records show Kisby was arrested in 2008 after a man she was with brandished a gun that went off in a struggle at an Egg Harbor Township motel. She pleaded guilty to aggravated assault and served her sentence in the county jail before being released in March.

Contact staff writer Amy S. Rosenberg at 609-823-0453 or arosenberg@phillynews.com.