A Fridley police school resource officer remained hospitalized Friday morning with injuries suffered when he was kicked in the head while breaking up a fight Thursday afternoon at Fridley High School.

Three teenagers were arrested after the incident, which occurred about 3:10 p.m. in the school parking lot at 6000 W. Moore Lake Parkway, Fridley police said.

Classes had just let out when a "significant physical altercation" broke out among students. Some of those involved did not attend Fridley schools, Superintendent Brenda Lewis said in an email to parents.

The resource officer intervened in the fight between two girls, ages 14 and 15, to prevent further harm to other students and staff, police said.

As the officer separated the students, a 16-year-old girl, who was not involved in the initial disturbance, kicked the officer in the head, police said.

The officer suffered "severe harm" and was taken by ambulance to North Memorial Health Hospital in Robbinsdale. The officer was in stable condition Thursday night, police said.

Law enforcement from several agencies responded to the scene, and two teenagers involved in the initial fight were arrested. The girl who allegedly kicked the officer also was arrested, police said.

The school district was investigating the incident with Fridley police and will take appropriate disciplinary steps for the students involved, Lewis said.

"The safety and security of our students and staff is our most important obligation," she wrote.

No other information was available.