LAKELAND, Fla — A Florida couple is accused of forcing a 13-year-old boy to kneel down for nine hours a day for 10 days in a row as a punishment for being bad at school, police said.

Albert Cusson, 57, and his wife Nancy, 47, from Lakeland, Fla., were jailed on child abuse charges Thursday after allegedly forcing the teen to kneel on a hard bathroom floor with his hands behind his back from 7 a.m. to 4 p.m. every day and beating him with a stick if he moved, the Polk County Sheriff’s Office said in a statement.

During the 10-day ordeal they made him sleep in a bathtub and fed him one “protein shake” a day containing meat, vegetables and other foods but then did not allow the boy to eat or drink anything after that, the statement added.

The boy managed to run away from the house Wednesday afternoon because he “could not take it anymore” and told a neighbor about the alleged abuse, police said.

Officers said the boy had blistered knees, red marks on his back and struggled to walk when they found him. He was taken to the Lakeland Regional Medical Center for treatment.

The boy, who was home-schooled, told cops that the couple planned to enforce the punishment for 20 days in a row.

The Cussons admitted forcing the boy to kneel and said it was because he misbehaved during school. Albert Cusson claimed he was punished in the same way by his father.

They denied the kneeling ordeal caused him injuries, and told detectives it was, “the only punishment that works for him.”

Police said the pair may face further charges as a nine-year-old girl also claimed they forced her to kneel for two days straight.

“There is no excuse for this type of deplorable behavior,” Sheriff Grady Judd said. “People who mistreat children are the worst of the worst. Jail is too good for them — the Cussons will be more comfortable in the county jail than this little boy was when he was in their care.”