First responders rushed the injured student to the hospital with a "minor stab wound," the Ventura County Star reported. They are expected to recover.
Fillmore High officials "detained" the student believed to be responsible for the stabbing in the assistant principal's office, the newspaper said. Authorities said they recovered the knife suspected to have been used to cut the other student.
The county sheriff's department deployed additional deputies on and around the campus. Police plan to maintain an expanded presence at the school through Tuesday and the rest of the week.
"We do not tolerate violence on campus and are taking all appropriate measures to respond to this situation," Fillmore Superintendent Christine Schieferle said, adding, "There is no ongoing threat on campus."
The superintendent said counselors would be available for students who may need to use the resource.
“Please know the safety of our students and staff is our utmost priority,” Schieferle told concerned parents in the statement.