The crash occurred near the intersection of Jackson Street and Sage Avenue around 2:20 a.m.
Area residents gathered around the horrific scene of the mangled and badly burned car. The violent crash was heard from several blocks away.
"Bam! It was an explosion. I didn't know what was going on, then I heard the helicopters," described Mike Schreifels, a Riverside resident.
According to police, two patrol officers saw the vehicle acting suspiciously.
"They were trying to catch up to the vehicle, and ultimately, not far from this intersection here, they observed the vehicle going probably close to 100 mph, plus turn their lights off, and continue to try and evade the officers," said Skip Showalter with Riverside police.
The officers were about to pursue the vehicle, but before they could, it slammed into a light post and a tree just past California Avenue on Jackson Street.
"All the officers saw from the distance they were, was what appeared to be like an explosion, and what that was, was the car crashing into the palm tree, which set it on fire," described Lt. Larry Gonzelez with Riverside Police.
Two people were ejected from the car during the crash. Officers used the license plate to identify the vehicle as a 1997 BMW. The identities of the victims were not immediately available.
"There was no doubt it was a fatal accident when they got on scene. Don't need to describe all the injuries in detail, but it was graphic," said Gonzelez.
Many bystanders were frantically calling family to make sure they were OK.
As for why the driver was evading police and whether alcohol played a role in the crash - all of that remains under investigation.
Jackson Street between Garfield Street and California Avenue was closed following the crash.