The board of a St. Louis charter school on Wednesday placed a principal on leave after he had police handcuff a 5-year-old and drive him around the block in a squad car to curb his unruly behavior.

Principal Sam Morgan (search) is on leave from Thurgood Marshall Academy (search) pending an investigation into last month's incident, board attorney Wayne Harvey said.

Morgan declined to comment Wednesday, but last week said he had spent more time on the boy "than any kid in this building, trying to steer him straight."

He said he had police "put the handcuffs on one arm, put him in the back seat of their car and drive him around a little bit."

Morgan added: "This kid is heading for the Department of Corrections at 5. He fights, strikes somebody practically every day on the bus. He's a constant disruption."

Morgan, a longtime principal at East St. Louis High School (search) in Illinois, also spent eight years working in the Department of Corrections.

The boy's mother, Aroni Rucker, said Wednesday her son had trouble adjusting to his first year of school and may have been disruptive, but he did nothing to warrant such treatment.

"They put handcuffs on my baby," Rucker said. "That's for adults who murder and kill. He's 5. He's in kindergarten."

Rucker said she was planning to pull the boy and her second-grader from the school at the end of the semester when Morgan told her last week that the kindergartner could not come back.

St. Louis police spokesman Richard Wilkes said the department was looking into the incident. "Handcuffing 5-year-olds is not a practice of the department," he said.

The University of Missouri-St. Louis announced in August that it would end its sponsorship of the charter school, meaning the school must find a new sponsor by June or close. The university placed the school on probation twice, citing fiscal mismanagement, board corruption, poor academic performance and high turnover in leadership — seven principals in five years.

University spokesman Bob Samples, part of the sponsorship team, said only that "it's inappropriate to handcuff a 5-year-old."