A wagon driver at Canada's Galgary Stampede was fined $12,500 after a horse had to be euthanized following a chuckwagon race collision, event officials said.Cliff Cunningham was initially fined $2,500 for wagon interference after his wagon tangled with one driven by Jim Knight in which one of Knight's horses suffered a broken leg, Postmedia News reported Sunday. The chuckwagon safety commission decided to increase the amount to send a strong safety message and to compensate Knight for the loss of the horse."Driver error will happen, but we want the drivers to do their utmost to avoid that type of incident in the future," safety commission chairman Stan Church said.The commission ruled Cunningham came too close to Knight's right lead horse, causing the horse to break a leg."I made a mistake," Cunningham said after the safety commission's announcement. "I'm not a rich guy and the fine hurts, but I didn't sleep last night and it wasn't because of the fine," he said. The Calgary Humane Society said it would investigate the incident and make recommendations at its annual meeting at the end of the Stampede."Obviously, we are saddened by any incidents where an animal is injured," spokeswoman Desiree Arsenault said.