Students at Edison High School were temporarily kept in their classrooms on Monday morning when two parents caused a disturbance at the school and police were called to defuse the situation, the school's principal said in a voice mail to parents.

Police were called to the northeast Minneapolis high school around 10 a.m. and officials placed the school on a Code Yellow alert for about 45 minutes. Students remained in their classrooms until the situation cleared when they were allowed to move to their third-period classes, said school district spokesman Dirk Tedmon.

Several squad cars were seen outside the school. The incident was contained to the entry area of the school, Tedmon said.

Principal Eryn Warne said school resource officers and staff joined outside law enforcement in resolving the situation when two parents caused "a disturbance in our school."

A man was cited for obstructing the legal process, and a woman was cited for disorderly conduct, according to Minneapolis police. In addition, two juvenile females were arrested for disorderly conduct and assault, and taken to the department's Juvenile Unit.

The nature of the disturbance was not disclosed.

"While this was an unfortunate incident, it was isolated and resulted from the poor choices of a few individuals," Warne said. "We must keep working together to keep our school community safe for all."

Police have yet to comment on the situation.

The incident comes after two fights involving students occurred last week in the school cafeteria.

"We are troubled that these incidents happened on our campus and within our student body. This kind of behavior must stop," Warne wrote in a letter sent to parents on Friday. "We will continue to work with our school and district teams to restore Edison to a place of peace and learning."

Police calls to Edison are down this year. Last year, the school reported eight assaults. This school year there has been one, Tedmon said.