“I just hoped it was a nightmare,” said his son Adam Díaz

Two Colorado brothers are devastated after their parents and two sisters were killed in a car crash over the weekend.

Thornton Police Department said in a press release shared on (formerly known as Twitter) that a Subaru driving at high speed struck the Ford SUV carrying the four victims around 7:30 p.m. local time on Saturday, October 26, “causing the gas tank to rupture and catch fire “. A third vehicle, a Chrysler pickup truck, was also struck.”

Francisco Díaz, Beatriz Núñez and their daughters Paola Díaz, 15, and Nataly Díaz, 10, died in the fire, KKTV, CBS affiliate And KMGH, ABC subsidiary reported.

Meanwhile, police said the driver of the Subaru was seriously injured and taken to hospital. The Chrysler driver was not injured. The accident remains under investigation.

Related: Dad whose 2 children were killed in car crash after mother allegedly became distracted speaks: ‘My heart is breaking’

Brothers Daniel and Adam Díaz, who were not in the car at the time of the accident, are in shock over their deaths. “We feel lost. We don’t even know what’s next,” Daniel told KMGH-TV. “It doesn’t even feel real yet.”

Their parents and sisters were heading to Walmart after going to church on Oct. 26, according to KKTV and KMGH.

“None of them were really answering their phones, so that’s when I came in,” Adam told KKTV. “I got there pretty quickly, but everything was already in flames. There was nothing they could do.”

“It just didn’t seem real to me. I was really hoping it was a nightmare,” he added.

Related: Nearly $1 million raised for Texas teen left orphaned after entire family dies in violent car crash

The brothers, who lived at home with family, said they were all close, KKTV reported. Now the brothers say they’re grateful to at least have each other.

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“(It’s hard) knowing that this time I’m going to go out and come home, (and my mother’s) won’t be waiting for me,” Daniel told the station.

Related: 10-year-old child, sole survivor of family murder-suicide, calls 911 after discovering bodies: police

A GoFundMe was set up to help the brothers with funeral expenses and more. As of Tuesday, October 29, the fundraiser has raised more than $67,000.

The organizer wrote: “Amidst their unimaginable grief, these two young survivors need our help to ensure they are supported during this difficult time.”

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