The parents of a 15-year-old who shot dead four students at a US high school with a gun bought by his father have been arrested after being charged with involuntary manslaughter, according to US media reports. The whereabouts of James and Jennifer Crumbley, the parents of shooting suspect Ethan Crumbley, had remained unknown for much of Friday, prompting authorities in Oakland County, Michigan to consider them fugitives. But police found them in an industrial building in Detroit — 40 miles from the scene of the shooting in Oxford — a block away from where their suspected vehicle had been found, Detroit police spokesperson Rudy Harper told CNN. The Crumbleys’ lawyers Shannon Smith and Mariell Lehman had previously told AFP that after leaving town on the night of the shooting “for their own safety,” the parents would be “returning to the area to be arraigned.” Yet local law enforcement officials told CNN the parents withdrew $4,000 from a money machine near Oxford on Friday and turned their phones off, heightening the mystery over their disappearance. Oakland County prosecutor Karen McDonald, in a rare move by law enforcement, had announced that each of the parents faces four counts of involuntary manslaughter. “These charges are intended to hold the individuals who contributed to this tragedy accountable and also send the message that gun owners have a responsibility,” McDonald said at a press conference. “While the shooter was the one who entered the high school and pulled the trigger, there are other individuals who contributed to the events on November 30.” As the manhunt escalated, US Marshals on Friday issued $10,000 rewards for information leading to the arrest of either parent and County Sheriff Michael Bouchard said the pair “cannot run from their part in this tragedy.” – Gun purchase – Four students, aged 14 to 17, were killed in the shooting at Oxford High School north of Detroit and six more were wounded, along with a teacher. Ethan Crumbley has been charged as an adult with state murder and terror charges. While school shootings carried out by teens occur frequently in the United States, it is unusual for parents to face charges. Four days before the shooting, James Crumbley bought the 9mm Sig Sauer semi-automatic handgun used by his son. Ethan was with his father at the time of the purchase at a local firearms store and the teen posted a picture of the gun on his Instagram account, writing “just got my new beauty today” along with a heart emoji. According to police, Ethan Crumbley recorded a video on his cell phone the night before the attack saying he was planning a shooting at the school the next day, but it was not posted online. That same day, a teacher at the school had observed Ethan Crumbley searching for ammunition on his cell phone during class and reported it to school officials. His mother was contacted by the school but did not respond to voicemail or email messages. McDonald said Jennifer Crumbley did exchange a text message about the incident with her son that day, writing: “lol I’m not mad at you. You have to learn not to get caught.” – ‘Don’t do it’ – The parents were summoned to the school on the day of the shooting after a teacher was “alarmed” by a note she found on Ethan Crumbley’s desk, McDonald said. It featured a drawing of a gun and the words “The thoughts won’t stop. Help me.” It also had a picture of a bullet, a person who had been shot and the words “my life is useless” and “the world is dead,” she said. The parents were shown the drawing at a meeting with school officials and advised that they needed to get the boy into counselling within 48 hours. McDonald said they resisted taking their son home and he returned to class. He later entered a bathroom, emerged with the gun, which he had concealed in his backpack, and opened fire. “The notion that a parent could read those words and also know that their son had access to a deadly weapon that they gave him is unconscionable and I think it’s criminal,” McDonald said. “I am angry,” she said. “I’m angry as a mother. I’m angry as the prosecutor. I’m angry as a person that lives in this county. “We need to do better in this country.” Ethan Crumbley fired at least 30 rounds, reloading as fellow students fled. McDonald said Jennifer Crumbley, when she heard about the shooting, had texted her son, saying: “Ethan don’t do it.” James Crumbley drove home and called the emergency line 911 to report that a gun was missing from his house and that he believed his son may be the shooter, McDonald said.