Three victims were treated at the scene by firefighters, then were transported to Northridge Hospital.
One person is reported as in extreme critical condition. The other two victims are reported as stable.
One victim at the scene could be seen apparently conscious and alert, talking on a mobile phone.
Police are searching the area for suspects. The suspects are described as one or more Hispanic males, fleeing in a red or maroon Chevrolet Suburban.
Traffic was backed up and being diverted from Roscoe Blvd.
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