The parents of the Michigan teenager accused of murdering four pupils at his high school plead not guilty to involuntary manslaughter charges on Saturday. The judge set their bail at $500,000 each and placed other requirements such as GPS monitoring, agreeing with prosecutors that they posed a flight risk. Oakland County prosecutor Karen McDonald told the hearing the Crumbleys withdrew $4,000 from an ATM while authorities were searching for them. "These are not people that we can be assured will return to court on their own," she said. On Friday, authorities said the couple were on their way to an arraignment – the reading of charges against them, then said they were missing. Local police said they were detained on Saturday morning. Their lawyer, Shannon Smith, said James and Jennifer Crumbley had left town “for their own safety” on the night after the shooting that left four pupils dead and seven other people injured, including a teacher. “They are not fleeing from law enforcement despite recent comments in media reports,” Ms Smith said. But a scheduled 4.30pm video arraignment did not take place as scheduled. Neither Ms Smith nor Mariell Lehman – the other lawyer representing the family – responded to questions about whether they were in touch with the Crumbleys, if the pair planned to turn themselves in, or if the arraignment was to take place. The US Marshals Service said its fugitive apprehension team from Detroit had worked with the sheriff's office on the search. Each parent on Friday was charged with four counts of involuntary manslaughter for their role in events leading up to the shooting and for buying their 15-year-old son, Ethan Crumbley, the gun reportedly used in <a href="https://www.thenationalnews.com/world/us-news/2021/12/01/oxford-high-school-shooting-three-students-killed-and-eight-injured-in-michigan/" target="_blank">the deadliest US school shooting of 2021</a>. Oakland County Sheriff Michael Bouchard had told CNN police searched for them after their lawyer told his office that the Crumbleys had stopped responding to messages. “If they think they're going to get away, they're not,” Mr Bouchard said, and added that a host of detectives, as well as the FBI and the US Marshals Service, were looking for them. At a press conference on Friday, Oakland County Prosecutor Karen McDonald detailed a series of warning signs she said the parents should have acted on. Four days before the shooting, Ethan accompanied his father to a gun shop, where the father bought a semi-automatic handgun, Ms McDonald said. Later that day, Ethan posted photos of the gun on social media, writing, “Just got my new beauty today” and adding a heart emoji. His mother posted the next day that the two of them were “testing out his new Christmas present”, Ms McDonald said. Under Michigan law, an involuntary manslaughter charge can be pursued if prosecutors believe someone contributed to a situation where the chances of harm or death were high. On November 21, a teacher saw Ethan searching online for ammunition on his phone during class and alerted school officials, who left messages for his mother that went unanswered. In a text message to her son that day, Ms McDonald said Jennifer Crumbley wrote: “LOL, I'm not mad at you. You have to learn not to get caught.” The morning of the shooting, a teacher discovered a drawing that Ethan had made depicting a handgun, a bullet and a bleeding figure. The words “blood everywhere” and “the thoughts won't stop – help me” were also written on the sheet, among other messages, Ms McDonald said. “It is impossible not to conclude that there is reason to believe he might hurt someone” based on the drawings, she said. School officials called a meeting with the Crumbleys after the drawing was found. “At the meeting, James and Jennifer Crumbley were shown the drawing and were advised that they were required to get … their son into counselling within 48 hours,” she said. She added that the parents “failed to ask their son if he had his gun with him or where his gun was located and failed to inspect his backpack for the presence of the gun, which he had with him". “The facts of this case are so egregious,” Ms McDonald said. Some time after the meeting, Ethan opened fire after coming out of a toilet with the gun, shooting at people in the hallway, police said. Ms McDonald said that Jennifer Crumbley, when she heard about the shooting, had texted her son, saying: “Ethan don't do it.” “This doesn't just impact me as a prosecutor and a lawyer, it impacts me as a mother. The notion that a parent could read those words and their son had access to a gun they gave him … it is criminal.” “I want to be really clear these [charges] are intended to hold individuals accountable and also send a message that gun owners have a responsibility,” Ms McDonald said. “When they fail to uphold that responsibility, there are consequences.” Parents in the US are rarely charged in school shootings involving their children, despite most minors using guns from a parent's or relative’s house, experts said. There is no Michigan law that requires gun owners to keep weapons locked away from children. Ms McDonald, however, suggested there is more to build a case on. “All I can say at this point is those actions on mum and dad’s behalf go far beyond negligence,” she told WJR-AM. “We obviously are prosecuting the shooter to the fullest extent … there are other individuals who should be held accountable.” <i>Agencies contributed to this report</i>