Updated

The manhunt for the two men involved in the deadly New Jersey mall carjacking has intensified, with rewards for their arrests increasing and forensic tests that may prove to be a watershed.

Two law enforcement sources told The Star-Ledger that forensics might provide the break they need in a case that, so far, has offered few leads.

Police are seeking two assailants who fled the parking garage of The Mall at Short Hills on Sunday after shooting Dustin Friedland when he refused to give up his keys because he knew his wife was in the car, The New York Post reported.

A law enforcement source told the newspaper the carjackers are believed to be black men in their 20s, based on surveillance video from a hidden security camera that captured the murder and statements from his wife, Jamie Schare Friedland, 27, who is also a lawyer.

The couple was carrying bags full of items and looked as if "they were trying to get all their Christmas shopping done in one night," a source at the mall told The Post. A source told The Star-Ledger that Friedland struggled with the men before he was shot.

Jamie Schare Friedland's uncle told the New York Post that the carjackers "should not have a day of peace, ever again."

"I want them dead," Schare told the newspaper. "In a heartbeat, I would like to see them dead because of what they did. And for what? What did they gain? It's just evil. "

According to a law enforcement, Friedland was shot in the head, the newspaper reported. He was pronounced dead at a hospital shortly before midnight.

Police said the two men drove off in the couple's silver Range Rover. The SUV was found Monday morning in Newark, on a residential street in the city's southern section a few blocks from Interstate 78, about eight miles from the mall.

A local anti-crime organization, the mall, and anonymous donors are offering the $41,000 reward for information leading to the arrest and conviction of the suspects.

The Associated Press contributed to this report. 

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