DETROIT, Dec. 3 (CNN) -- 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 — 60 kilometres 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”.