It happened on International Boulevard near 105th Avenue on Friday afternoon.
The attack has Oakland police concerned that this is an indication of crime trending upwards.
"I have been a police officer for 25 years and have never encountered this. It is probably something you're not expecting," said Lieutenant Tim Dolan with the Oakland Police Department.
As he explains, two officers were stopped at a red light on International Boulevard on Friday afternoon. The patrol car had its windows down. That's when the officer on the passenger side was hit in the face.
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"The officer was able to get out and defend himself. And the other officer helped out, too, to take the person into custody," said Dolan, who is also vice president of the police union.
Dolan said the officer was transported to the hospital and evaluated. He is now back home.
There is no indication that the officer was targeted. Oakland police would not reveal much about the suspect, only to say that he was taken into custody and placed on "a mental health hold."
"We can't get into specifics about who the (suspect) is. There are privacy rights related to that. And that case hasn't been charged yet. And I know that our criminal investigations division is following up with charging this for assaulting the officer," Dolan said.
Oakland police would not disclose the identity of the officer, but did say that the officer was undergoing training and is a graduate of the Oakland's most recent police academy from last December.
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The police union claims crimes are trending higher in Oakland so far this year compared to 2024 and that an assault like this is indicative of the what's happening on the streets of Oakland at a time when OPD is facing budget cuts.
"Homicides are up this year, compared to where we were at last year. I was looking at some of the statistics this morning. I think shootings are up 14% as well," Dolan said. "I am worried that crime is trending up and our staffing levels are going down. I'm a little worried about the future of how we are going to police the city if we keep losing officers."
Oakland city leaders did not return requests for comment on Saturday.
Police are asking anyone with information about the incident to contact the Oakland Police Department.