CHP says the party bus was likely targeted and not a random crime.
Around 2:25 a.m., California Highway Patrol officers responded to a report of a highway shooting on the eastbound Interstate Highway 80 transition to southbound Interstate Highway 880, according to CHP officials.
The bus was coming from San Francisco and had just exited the Bay Bridge when a vehicle drove alongside the bus and opened fire.
One of the occupants suffered critical injuries and was taken to the hospital. That victim is reported to be in stable condition as of Saturday morning, the CHP said.
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Three other occupants suffered minor injuries. Officers with the Oakland Police Department assisted the CHP with the investigation.
None of the bus' occupants would cooperate with law enforcement and several occupants were combative, according to CHP officials.
"No one provided a statement, no one described the suspect car. One woman assaulted our officer as we attempted to interview her," said Officer Daniel Hill, with the CHP.
One female occupant allegedly assaulted an officer who was trying to interview her.
Another female occupant who was injured got into an altercation with emergency medical personnel while she was being taken to the hospital and ultimately forced her way out of the ambulance. Her whereabouts are currently unknown, CHP officials said.
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The suspect vehicle is being described as a red SUV, occupied by two gunmen, according to the CHP.
The CHP closed the transition road for nearly five hours as they investigated.
The shooting marks the eighth freeway shooting in the East Bay since November, 2015.
Anyone with information about the incident is asked to contact the CHP at (707) 551-4100 or (510) 622-4609. Witnesses have the option of remaining anonymous.
Bay City News contributed to this story.