Updated: Thu Mar. 29 2007 9:17:24 PM

toronto.ctv.ca

A five-year-old boy who survived miraculously after falling nine floors was probably playing on a mountain bike when he toppled over the balcony railing, police said Thursday.

Young-Jin Kim is expected to make a full recovery. He fell from the apartment balcony Wednesday morning, landing on his back on a grassy courtyard just after 10 a.m.

Det. Brian Ritchie told the Hamilton Spectator that police believe the boy climbed onto a bike on the balcony and tumbled over the metre-high railing.

"He's probably the luckiest person I've ever come across to have gone down 90 feet and hit soft ground,'' said Ritchie. "If it had been two weeks ago, it might have been a different story.''

Paramedics rushed the boy to McMaster University Medical Center with two broken legs, a broken pelvis and other internal injuries. The child underwent a three-hour surgery to repair his legs. He suffered no internal or neurological injuries.

The boy's father told CTV News in a phone interview from the hospital that he believes it's a miracle the child survived.

The child's mother was said to be cleaning the apartment when she noticed her son was missing. She then heard moaning and screams. The mother looked over the balcony and saw her boy lying on the ground.

The family is from Korea and moved to Hamilton three years ago.

The Hamilton Police Child Abuse unit is investigating, as is the Children's Aid Society.

With a report from CTV's John Musselman