To maintain order in special education classrooms, some Minnesota schools are turning to police.

That strategy unnerves many parents, who have complained to the state that their children are sometimes treated like criminals for disrupting class. Each year, dozens of disabled students statewide are arrested by officers stationed at schools for offenses ranging from disorderly conduct to assault, school officials acknowledge.

But police officers have occasionally exceeded their duties by acting as informal disciplinarians, state regulators have found. In some cases, students complained that police officers were used to intimidate them, either through threats or the improper use of handcuffs.

According to the state, police can intervene only in an emergency or if they are responding to a report of criminal behavior.

Kadaan Christians was placed in handcuffs five times last fall by a police officer at his school in Starbuck, a small town in western Minnesota.

The 9-year-old's offense? "I was having a temper tantrum," said Kadaan, who has autism. His school specializes in treating children with behavioral problems.

On Nov. 13, a report said Kadaan got mad and lay on the floor because he didn't get his work done on time. The school's police officer intervened when Kadaan started hitting the floor. As the officer escorted Kadaan to the timeout room, Kadaan began spitting and "punching wall/staff." The officer placed him in handcuffs for 15 minutes.

Kadaan said his legs also were restrained and a cloth spit-guard put over his face.

"It hurt," said Kadaan, who said his legs and arms were covered in bruises after the incident. "The officer who handcuffed me was mean."

His mom is outraged by the repeated handcuffing. "I don't think that is right," Courtney Christians said. "It is behavior he can't control. It is part of his disability. … It tripled his anxiety about going to school."

Officials with Minnewaska Area Schools declined to discuss the incidents but said they consider handcuffing a student a "last resort" to be used when other calming methods fail.

Carla Ptacek, the district's special education director, said "very few students" have been handcuffed.

Ptacek said parents are not asked to approve the use of handcuffs or other mechanical restraints on their children. Such permission is no longer required under state law. That protection was removed in 2009 when lawmakers revised the rules regarding the use of restraints and seclusion in Minnesota.

State officials said there is nothing they can do about the Starbuck school's use of police.