FARMINGDALE, N.Y. (CBSNewYork) — Police are looking for the occupants of a stolen car and a second vehicle that were operating so erratically, they caused a fatal crash on the Southern State Parkway in West Babylon on Monday.

A 75-year-old Holbrook grandfather lost his life. Police said the people in the stolen car got away in the second car.

CBS2’s Carolyn Gusoff spoke with the victim’s heartbroken family.

It was a devastating sight on the Southern State for a mother and daughter who happened to be driving by.

“She says, ‘What’s daddy’s license plate number?’ And she starts calling out the letter one after the other, and she says, ‘Oh my God, that’s daddy,'” said Carol Riggs, the victim’s wife.

Richard Riggs (Photo: Riggs family)

“Horrendous. I was in a state of shock, and my daddy, he died instantly,” Samantha Guglieri said.

“I was leaving my husband on the road and there was nothing I could do,” Carol added.

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Carol was married for five decades. Her beloved Richard, 75, was always on the road as a salesman of auto parts.

On Monday, near Belmont Lake State Park, witnesses say two erratic drivers in a Range Rover and a Jeep weaved in and out of traffic for miles, cutting off other drivers. As they dangerously passed between two cars, Richard Riggs lost control and struck a tree.

State police say the two people in the Range Rover got into the Jeep and fled, adding the Range Rover they left behind was stolen.

“We are distraught, we’re heartbroken, inconsolable,” Guglieri said.

“This was murder. I look at it as it was murder. They killed him. They took him away from his family and changed everybody’s life,” son-in-law Chris Agerenza added.

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Described as a gentle giant who had no plans of retiring until he turned 80, Richard Riggs was a grandfather and champion of two deaf daughters, and was known as the most careful driver.

“Fifty, 55, always aware of his surroundings. He was a great driver. He did it for a living,” Agerenza said.

“They had no respect for human life and he didn’t deserve to die like this,” Carol Riggs said.

State police say witnesses saw the two people in the stolen Range Rover flee in a white Jeep Grand Cherokee.

“This was a senseless tragedy. The suspects that we are looking for drove recklessly, causing the death of Mr. Riggs,” State Police Capt. Christopher Casale said.

The family is pleading for witnesses to come forward to help police make arrests.

The stolen vehicle was taken from an East Garden City driveway on July 5, police said.

Carolyn Gusoff