PEORIA, AZ (3TV/CBS 5) -- Police are investigating impairment after a serious crash in Peoria early Friday morning.
The crash happened near 85th and Northern avenues around 2:30 a.m.
Fire officials said four people were hurt in the two-vehicle rear-end collision.
Police say both of the drivers were conscious and one of the patients had to be extricated from a vehicle.
All four people were taken to a hospital. Fire officials say three of the four are in critical condition, but police believe the injuries are not life-threatening.
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Impairment of one of the drivers is suspected, according to police, but they are still investigating.
Northern Avenue is closed in the area while they investigate the collision. Drivers are advised to seek an alternate route.
No other details were released.
Stay tuned to Arizona's Family for developments.