According to WREG-TV in Memphis, Tennessee, the incident occurred on Sunday after 11-year-old Aalando Perry rode on the Branson Coaster in Branson, Missouri.

While speaking with WREG-TV, the boy’s grandmother, Shelandra Ford, said Perry attempted to ride the coaster with his brother, but they were told the boy would be fine riding by himself.

“All the kids said the roller coaster stopped, and my grandson who is vision impaired got up and preceded to get off the roller coaster, and the roller coaster restarted backed up, and he fell off and got entrapped under the rails, and he was there for about an hour and a half,” Ford told WREG-TV.

In a Facebook post, Branson Professional Firefighters Local 152 said that fire officials, along with members of the Branson Police Department, “responded for a person entrapped at the Mountain Coaster,” at around 7:30 p.m. local time on Sunday.

Officials found Perry “heavily entrapped” under the coaster.

“Rescuers worked on scene for an hour and forty minutes on a very difficult technical rescue,” the Facebook post said.

After rescuers were able to free Perry from under the coaster, he was airlifted to Springfield Hospital, with “very serious injuries.”

“The accident is under investigation,” the Facebook post said.

While speaking with WREG-TV, Ford explained that her grandson’s arms and legs were severely damaged.

“They are talking about amputation,” Ford told WREG-TV. “He has had two surgeries so far since this morning—skin grafts, and he is going have at least six or seven more before they can even see progress. He’s heavily sedated and in a lot of pain.”

According to WREG-TV, Ford said that her grandson suffers from Marfan Syndrome, a genetic disorder that affects the body’s connective tissues. Ford told WREG-TV that it has caused Perry to become visually impaired and he has only 15 percent of vision in one eye.

As doctors continue to treat Perry, his grandmother told WREG-TV that she is happy he is still alive but noted that her other grandson explained to the roller coaster’s worker that Perry is visually impaired.

“If they couldn’t both ride in the same cars together, they shouldn’t have allowed him to get on the ride, period,” Ford told WREG-TV.

Newsweek reached out to the Branson Fire Department for further comment but did not receive a response in time for publication.