ELIZABETH, N.J. (AP) -- A Salvadoran immigrant's wad of payday cash proved irresistible for a group of teenagers charged in his videotaped beating death, as well as for the nurse who eventually managed to pocket it when the victim arrived at the hospital, authorities said.

The confrontation was not an instance of bias, Union County Prosecutor Theodore Romankow said Friday, but "a crime of opportunity." But they chickened out, authorities said.

If this man were a Caucasian, an African-American, or a Chinese person they would have done the same thing to him," Romankow said.

Police were able to piece together the events, in part, from a cell phone video taken by one of the youths and circulated among friends.

A group of 14 teenage girls and boys were hanging out in the upscale New York City suburb of Summit around 9 p.m. Saturday, July 17, when they spotted 47-year-old Abelino Mazariego sitting on a bench in the Summit Promenade, a small park with a fountain and benches tucked into an alleyway along the main business corridor, authorities said.

The victim was carrying a wad of about $640 in cash, authorities said; he had just been paid from his job as a dishwasher at a local Indian restaurant. After work, Mazariego purchased liquor at a nearby store and sat drinking on the park bench, where he took off his shirt and was "minding his own business," Romankow said.

It was a crime of oppportunity," he said. "They saw this man had money, perhaps seeing a man who was intoxicated and defenseless. It's a sad situation.

A juvenile now charged with murdering the victim allegedly approached him, sat beside him, and either spotted the cash or was shown it by Mazariego, police said. The teen then allegedly conspired with four others to rob him.

Police say 18-year-old murder suspect Khayri Williams-Clark pulled Mazariego's shirt over his face, while an unidentified 17-year-old juvenile and 19-year-old Nigel Dumas each punched him full-force in the jaw, Romankow said. Two other juveniles stood watch, authorities said.

The five teenagers ran away when they saw Mazariego slump, bloodied, onto the bench, according to Romankow. They forgot the victim's cash and watch but returned a short while later to try to retrieve it. By the time they came back, Romankow said, the teens saw people coming to Mazariego's aid and did not approach.

People who saw Mazariego slumped and bloodied on the bench, as well as emergency and hospital personnel, did not initially realize he had been attacked and punched, resulting in brain bleeding, Romankow said.

At Overlook Hospital in Summit, Mazariego's family members noticed his money was missing and told authorities, who charged nurse Stephan Randolph, 39, of Flemington, with third-degree theft for allegedly taking the $640 from the unconscious victim.

Mazariego died in the hospital days later without ever regaining consciousness.

Williams-Clark and the unidentified 17-year-old, both of Summit, and Dumas, of Morristown, face felony murder charges, and prosecutors are seeking to try the juvenile as an adult.

Two other juveniles, ages 15 and 17, were arrested Thursday and face aggravated assault and robbery-related charges for allegedly standing guard as the attack took place. No other teens, including the one who videotaped the attack, will be charged, authorities said.

Investigators had no evidence suggesting the teen who shot the video was involved in the beating, assistant prosecutor Jim Donnelly said. And, he said, filming an incident doesn't make someone an accomplice under New Jersey law.

New Jersey's public defender's office, which is representing Dumas and the juvenile charged with murder, has declined to comment. A spokesman said the office is no longer representing Williams-Clark, who previously pleaded not guilty to an initial charge of manslaughter. The name of his new lawyer wasn't immediately known.

It also was not clear whether Randolph, the nurse, had a lawyer. Romankow said Friday that he had been fired.