Fireworks set off without permission by a traffic police officer during a late-night parade rehearsal in Rome startled dozens of horses on Friday, sending them bolting through the capital and injuring several riders.The unexpected bangs caused panic among the ceremonial horses, some of which had riders while others were being led by hand, during preparations for Italy's Republic Day parade taking place just before midnight, local time.About 35 horses fled onto the busy Via Cristoforo Colombo, where some drivers filmed them as they galloped down the road.The last horse was recovered at dawn about 14 kilometres from the scene.Several riders were thrown from their horses due to the incident, including a 22-year-old soldier who suffered broken ribs and a punctured lung but was not in a life-threatening condition.About 15 horses were also injured, but none were put down, police said.Mario De Sclavis, commander of Rome's police force, told Sunday's Corriere della Sera newspaper that the incident "discredits the image of the corps [police force] and its officers".Reuters