At least six people were injured in a shooting at a school campus in Oakland, on Wednesday, authorities in the northern California city said.

The shooting occurred at Rudsdale Newcomer high school, said Darren Allison, the Oakland assistant police chief.

The school serves students who are at risk of not graduating and have recently immigrated to the US after fleeing their home countries “because of violence and instability”, according to the school’s website.

It is one of four adjacent schools that serve middle and high school students on Fontaine Street in east Oakland.

“The victims were affiliated with the school and we are determining the affiliation at this time,” Allison said, although he declined to say whether any students or teachers were involved.

Paramedics transported six patients to hospitals, all with gunshot wounds, according to Oakland fire department spokesperson Michael Hunt.

Three of the wounded were admitted in critical condition at Highland hospital. The condition of the other three were unknown, officials said.

Wednesday’s shooting comes as Oakland has been grappling with more than two years of elevated gun violence, a rise in violence that began early in the pandemic.