HOUSTON --A horse was killed after a car slammed into a man riding it in north Houston last night. It happened at Lomax at Knight just before 9pm. Police say an SUV struck the man and his horse when the rider crossed in front of the vehicle. The man was knocked off his horse but wasn't hurt. The horse managed to stand up on its own, but the Houston Humane Society says the animal was severely injured. They determined the horse needed to be put down.