PATERSON, N.J. (CBSNewYork) — The cause of what witnesses said was a head-on crash in New Jersey is under investigation.

The accident shut down parts of Route 20 in Paterson on Wednesday morning, CBS2’s Christina Fan reported.

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Neighbors said it was a wrong-way collision at such a high rate of speed, the vehicles were broken down to pieces.

Multiple families said it was the worst accident they’ve ever seen.

Chopper 2 showed the crushed remains of the early morning multi-vehicle crash.

Chopper 2 over the scene of the accident on Route 20 in Paterson, New Jersey on Feb. 24, 2021. (Photo: CBS2)

Sal Carrubba saw it all firsthand and spoke to CBS2 via FaceTime from work.

“Nobody hit the brakes because there was no time. I don’t know where the blue car came from and it hit so hard, the blue car spun around,” Carrubba said.

Carrubba’s house directly faces the highway near 17th Avenue.

He said a white Honda was traveling southbound on Route 20 when a blue Kia going in the wrong direction crashed into the car head-on. A third vehicle was also hit.

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“I thought they were gone. I mean, just the way the impact and the look of the cars. That’s why I didn’t even want to look. I said, just call the ambulance,” Carrubba said.

“When I got up it was around like 5,  5:30. Then I heard a loud bang and then I came to the window and I see all the cars and lights,” resident Ella Coney added.

Investigators say four people were injured and transported to the hospital. The 20-year-old driver of the Kia, his 22-year-old passenger, and the 63-year-old driver of the Honda all suffered serious injuries.

The driver of the third vehicle was treated and released.

All morning, the Passaic County Prosecutor’s Office could be seen taking notes and photos, re-constructing the accident site.

The severe front-end damage was a frightening sight.

“It’s chilling, really. It’s terrible to see. My heart goes out to everybody involved,” resident Michael Symonds said.

While investigators haven’t released the cause of the crash, families said speeding and drag racing have been a long-time problem on the stretch of road, adding accidents are routine. However, they said none have ever looked this severe.

“This is a real traffic accident blackspot here. We see crashes every year, several times a year,” Symonds said.

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CBS2’s Christina Fan contributed to this report

CBSNewYork Team