A five-year-old Japanese boy was burned to death when a climbing frame built for an arts festival in Tokyo suddenly caught fire, reports and authorities said. The unusual blaze on Sunday sent flames several meters high into the evening sky, witnesses in the Japanese capital said. A man believed to be the boy’s father cried out for help in tears, shouting, “My child is inside!”, the Asahi Shimbun newspaper and other dailies reported. However, Kento Saeki was pronounced dead at the hospital, police said, without giving an official cause of death. Newspapers reported that he suffered suspected fatal burns. An unconfirmed number of other children reportedly managed to escape. The frame, built by university students, was one of the exhibits at Tokyo Design Week, which was attended by many families over the weekend. The cause of the fire has yet to be officially determined, police and firefighters said. However, Jiji Press quoted an investigative source as saying that a broken light bulb was found at the scene, which may have ignited sawdust on the frame of the climbing frame. The dead boy’s father and another man who took part in the desperate rescue operation reportedly suffered burns, but they were not life-threatening. The event organizer and the university apologized for the loss of life, while netizens expressed their condolences. “It is painful just to think of the feelings of the father who could not save his own son who was on fire,” one tweet said.