By CBSLA Staff

FONTANA (CBSLA) — Two people died and three others were critically injured Wednesday after a multi-vehicle crash in Fontana.

According to the Fontana Police Department, the crash happened at about 2:45 p.m. near the intersection of Sierra and Ramona avenues. Sierra Avenue was closed for hours during the investigation.

“We started getting 911 calls of a reckless driver coming down Sierra at a high rate of speed,” Officer Daniel Romero said. “One of the callers estimated the speed to be over 100 miles an hour.”

That alleged reckless driver was behind the wheel of a green SUV that slammed so hard into two other vehicles that the SUV flipped multiple times. The driver’s estimate speed left the other drivers — one in a red Honda and the other in a white Mustang — no time to get out of the way when he came barreling toward him.

“I don’t know why he was driving so fast through here,” a neighbor said.

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When officers arrived on the scene, two people had already died from their injuries. Three others, including the driver of the green SUV, were taken to area hospitals with critical injuries.

“I’m very sad,” Abdul Eltahir, another neighbor, said. “Very sad.”

But nobody was more devastated than a man seen sitting near the crash site in a black car. He told CBSLA that his fiancée was killed in the crash. He said she was not answering her phone so he followed the phone’s GPS to where his worst fear was confirmed.

He also said her mother, who was in the passenger seat of the red Honda, was killed. His fiancée’s two younger brothers were also in the vehicle and had to be airlifted to a local hospital. The man was later joined by his family and his fiancée’s family at the crime scene.

“It’s just really sad these two people had to pass away because of one person that doesn’t think of what they’re doing,” a neighbor said.

Police have not yet determined whether or not drugs or alcohol were involved in the crash, but they said there have been a few other speed-related fatal crashes on this stretch of Sierra Avenue and that people needed to slow down.

“In the middle of the daytime when there’s a lot of people out and about, couldn’t have happened at a worse time,” Romero said.

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Authorities have not yet identified the deceased.