(Reuters) - A 13-year-old boy's lower right leg was amputated after a teacher at a Columbus, Georgia, school slammed him to the floor three times, an attorney for the boy’s family said on Friday.

Seventh-grader Montravious Thomas was hurt last month when he tried to leave a schoolroom at the AIM/Edgewood Student Services Center to call his mother and an altercation ensued, lawyer Renee Tucker said.

The AIM program is for students who have been temporarily removed from their schools because of behavioral problems or for rule-breaking.

"As part of that altercation, it's our understanding that there were three different occasions on which he was picked up and reportedly slammed to the floor," she said by telephone.

Tucker said a civil lawsuit was planned because of failure to render medical aid at the school. The teacher, Bryant Moseley, carried Thomas over his shoulder to a school bus to be taken home, she said.

In a statement, the Muscogee County School District said that it was committed to a thorough review of the reported incident. The teacher is employed by contractor Mentoring and Behavioral Services and is not now providing services to the school district, it said in a statement.

It said that Mosley was trained in MindSet, a system of managing aggressive behavior, and to meet Georgia state requirements on physically restraining students.

"It is our understanding that there were issues concerning the safety of the child and others in the room, which called for the use of restraint per state guidance," the school district said.

Mentoring and Behavioral Services, which is in Columbus, referred questions to its attorney, Robert Poydasheff Jr. He was not immediately available to comment.

Tucker said Thomas suffered a dislocated right knee and a fractured tibia that severed a nerve and veins. He was airlifted to an Atlanta hospital and underwent about four surgeries but had to have his leg amputated below the knee this week because of lack of blood flow, she said.

Tucker said Thomas was the only student in the room, along with three or four adults, including an assistant principal.

A Columbus Police Department spokesman was not immediately available to comment on whether any charges had been filed.

(Reporting by Ian Simpson; Editing by Steve Orlofsky)