@abc7chicago: Roller coaster rides reportedly turned from thrills to scares for a few recent guests at Worlds of Fun. A couple said they were riding the Mamba, the tallest coaster at the Kansas City theme park, on Oct. 11 when a young girl behind them announced that her seat belt was not latched. "It was completely undone," said Chris Evins, who helped hold her down. "And there was this big of a gap between her and the lap bar." Evins and his wife held onto the girl and her friend next to her as the 205-foot-tall coaster went on.