A Michigan prosecutor last night filed charges against the parents of a 15-year-old boy accused of fatally shooting his classmates at an Oakland County high school this week.

James and Jennifer Crumbley, parents of shooting suspect Ethan Crumbley, face four counts each of involuntary manslaughter, Oakland County prosecutor Karen McDonald said.

Ms McDonald said the Crumbleys bought a semiautomatic handgun as a gift for their son, who days later allegedly used it to kill four of his Oxford High School classmates and wound seven people.

Oakland County authorities said they are searching for the Crumbleys.

Authorities said that James Crumbley bought the 9mm Sig Sauer SP 2022 pistol on November 26, while an employee of Acme Shooting Goods in Oxford, Michigan, confirmed that Ethan accompanied his father for the purchase, Ms McDonald said.

The details from the forthcoming criminal complaint against the parents reveal the Crumbleys not only bought the gun for their son, but failed to secure it, leaving it in an unlocked drawer of their bedroom.

Shortly after his father bought the gun, Ethan Crumbley posted a photo of it to his Instagram page writing a caption interspersed with heart emoji that read, “just got my new beauty today, Sig Sauer nine millimetre. Any questions I will answer.”

His mother captioned a post of her own on social media that read: “Mom and son day testing out his new Christmas present.” Ms McDonald said the post was a reference to a visit the two made to a gun range.

But officials at Oxford High School first raised concerns about Ethan Crumbley’s behaviour on November 29, when a teacher noticed him using his cellphone to search for information on firearm ammunition. Jennifer Crumbley did not respond when the school contacted via voice mail about her son’s “inappropriate” search, Ms McDonald said.

Instead, she exchanged a text message with her son that read, “LOL I’m not mad at you. You have to learn not to get caught.”

On the morning of the shooting, the Crumbleys had been summoned to the school after a teacher found a drawing in Ethan’s desk showing a handgun pointing at the words “The thoughts won’t stop. Help me.”

The Crumbleys “resisted the idea of their son leaving the school at that time”, Ms McDonald said, and he returned to class.

Less than three hours later, the first 911 calls poured in about shots fired at the school.

“Ethan, don’t do it,” Jennifer Crumbley texted to her son when news of the active shooting went public, Ms McDonald said.

Moments after the text, Ms McDonald said James Crumbley drove home to check on his son’s gun. When he found it missing, he called to report it to 911 and said his son might be the shooter.

© Washington Post