FRANKFORT — (CNN) A Kentucky sheriff’s deputy now faces a federal lawsuit for handcuffing elementary school children who were acting out as a result of their hyperactivity disorder and other disabilities, the American Civil Liberties Union said.

The ACLU is suing Kenton County sheriff’s Deputy Kevin Sumner, who works as a school resource officer at Latonia Elementary School in Covington. Sumner is accused of handcuffing an 8-year-old boy and a 9-year-old girl, who both have attention deficit hyperactivity disorder.

Cell phone video obtained by the ACLU captured one incident in which Sumner talks to a boy handcuffed in a chair. The boy is so small that he’s handcuffed not around the wrists, but around his biceps.

“You don’t get to swing at me like that,” the deputy says as the boy cries. “You can do what we’ve asked you to, or you can suffer the consequences.”

“Ow, that hurts!” the boy cries.

The deputy tells the boy what he’ll need to do to get unshackled.

“If you want the handcuffs off, you’re going to have to behave and ask me nicely,” he said.

“And if you’re behaving, I’ll take them off, but as long as you’re acting up, you’re not going to get them off.”

The handcuffs were removed after about 15 minutes, the ACLU said, citing school records.

The ACLU said the girl was twice handcuffed behind her back by her biceps and was also in pain.

“Both children were being punished for behavior related to their disabilities,” the ACLU said in a statement.

All three incidents happened last fall.

The group is suing on behalf of the two children, claiming Sumner violated the Americans with Disabilities Act.

The suit seeks a change in policies by the Kenton County Sheriff’s Office and additional training for school resource officers in dealing with young children and children with special needs. It also seeks an unspecified amount of monetary damages against Sumner.

“Shackling children is not OK. It is traumatizing, and in this case it is also illegal,” said Susan Mizner, disability counsel for the ACLU.

“Using law enforcement to discipline students with disabilities only serves to traumatize children. It makes behavioral issues worse and interferes with the school’s role in developing appropriate educational and behavioral plans for them.”

CNN has not reached Sumner or anyone representing him for comment.

Sumner’s attorney, Robert Sanders, told the Lexington Herald-Leader that Sumner put the children in handcuffs because “they were placing themselves and other people in danger of harm and that’s what the book says to do.”

“Kevin Sumner is one of the best and most highly trained school resource officers in Kentucky,” Sanders told the newspaper.

“He’s a teacher who left that profession to become a police officer. He’s totally devoted to kids and schools and education.”

According to an investigative report cited in the lawsuit, Sumner said the boy “swung his arm and attempted to strike him with his elbow,” but the deputy blocked the boy’s elbow with his hand.

Kenton County Sheriff Chuck Korzenborn is also named in the suit, accused of failing to properly train and supervise Sumner.

“Kentucky’s school personnel are prohibited from using restraints, especially mechanical restraints, to punish children or as a way to force behavior compliance,” Kim Tandy, executive director of the Children’s Law Center, said in a statement. “These regulations include school resource officers. These are not situations where law enforcement action was necessary.”

The Kenton County Sheriff’s Office declined to comment to CNN.

In a statement, Covington Independent Public Schools said it will not comment on the lawsuit, per district policy.

“However, the school district has fully cooperated with the children’s legal counsel, as well as the Sheriff’s Office in looking into the complaints and we will continue to do so,” the statement said.

The school district added that school resource officers “are assigned in the schools to maintain the safety of students and staff” and “act in accordance with their training as law enforcement officers.” But they “are not called upon by school district staff to punish or discipline a student who engages in a school-related offense.”

The boy’s mother said her son was traumatized from being handcuffed.

“It is heartbreaking to watch my little boy suffer because of this experience,” she said, according to the ACLU.

“It’s hard for him to sleep. He has anxiety, and he is scared of seeing the officer in the school. School should be a safe place for children. It should be a place they look forward to going to. Instead, this has turned into a continuing nightmare for my son.”

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