An eight year old boy was released Monday from Norwalk Hospital after being injured on Sunday when a ride malfunctioned at a carnival in Norwalk, Connecticut. The boy was one of 13 people who were sent to the hospital after a rotating swing ride abruptly stopped, causing the riders to crash into one another and into the ride. The other 12 patients were treated and released Sunday. State Police say they have determined the accident was caused by a mechanical failure. The owner of Stewart Amusement Company, Richard Stewart, said Monday that the drive system of the swing ride locked up for some reason. He says workers will disassemble the equipment to see if they can determine what happened. Stewart says the 30 year old ride had no previous problems and authorities inspected it before the fair began Friday.