Officers detained two individuals, according to OPD.
Emergency crews were called about 7:42 p.m. to the school, where two adults, a male and a female, were wounded by gunfire in a parking lot, said Oakland Fire Department spokesman Michael Hunt. They were taken to a hospital by ambulance and as of 9 p.m. were in stable condition. It is unclear if those two are students.
UPDATE: 1 arrested, 2 injured after shooting during Oakland's Skyline High School graduation event: police
Another person was also reportedly hit by gunfire and showed up at a hospital by their own means, but police didn't respond to a request for information about a third injury in the shooting.
Witnesses described what they saw.
"You start seeing the people running and everything like that," said a man by the name of Larry, "I started ducking down and I started ducking down and tried to. You're just trying to figure out if it's some pop, like celebration or what."
"They were poppin' off the little confetti poppers and I thought it was all cool and then everyone started running. We saw hella smoke. I don't know what happened but it sounded like someone was driving by. Saw the smoke, heard the poppin', it was just a series that sounded like somebody had an automatic gun at some point and someone had a non-automatic gun at some point," said Jay Hackett.
A student tells us he was taking photos with his friends after the event when he heard gunshots.
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He says people started running - before staff escorted them off the school's field and into the locker room.
A cellphone video shared with ABC7 News shows some of the moments that played out. There appears to be some sort of a fight and then gunshots can be heard along with yelling.
Police are calling this an isolated incident.
Bay City News contributed to this report.