Three teenagers and a woman have been arrested for an alleged armed robbery of a teenage girl trying to buy marijuana, according to the Waterloo Cedar Falls Courier. Police say the 17 year old girl went to Lafayette Park around 9:45 p.m. Wednesday, where she had made plans to buy marijuana. While there she was approached by a 15 year old and two 14 year old boys, one of which brandished a revolver. The boys allegedly forced the girl to transfer $120 on a phone app. The teens then ran to an SUV across the street. A short time later, police pulled the SUV over. They found the gun inside and charged the boys with first degree Robbery. They also arrested the driver, 40 year old Catherine Hydle, and charged her with Possession of Marijuana With Intent to Deliver. She was released pending trial.