A bus raced out of control down a set of steps and into a busy square during the Stockholm Marathon on Saturday, injuring six people and causing a panic among spectators, AP quoted officials and witnesses as saying. Karolinska Hospital said it had received a seriously injured man, two women with lighter injuries and a 1-year-old child with light injuries. Two people with shoulder injuries were also taken to Stockholm South General Hospital, that hospital said. The victims were all pedestrians and no one on the bus was hurt. Stockholm Public Transport spokeswoman Gunilla Glans said it is unclear what caused the crash and that the bus operator Keolis has started an investigation. She said the bus driver was also taken to hospital, but had not been injured.