The parents of the Michigan school shooting suspect have been arrested in a Detroit basement hours after going on the run, police say.
James and Jennifer Crumbley were found unarmed hiding in a warehouse after a tip-off from someone who saw their car.
The couple had failed to show up in court on Friday after being charged with involuntary manslaughter.
They denied the charges after being detained.
Prosecutors say Ethan Crumbley, 15, used his father’s gun to shoot classmates in the nearby Michigan town of Oxford, killing four and wounding seven.
His parents are accused of ignoring warning signs before their son’s alleged rampage.
Earlier the US Marshals offered a $10,000 reward for information leading to their arrest.
Reports in the US say police knew the couple had withdrawn $4,000 from an ATM in Rochester Hills on the edge of Detroit and had turned off their mobile phones.
Ethan Crumbley is alleged to have opened fire on fellow students and teachers at his school in Oxford, about 35 miles north of Detroit, on Tuesday.
The four killed were Tate Myre, 16, Madisyn Baldwin, 17, Hana St Juliana, 14, and Justin Shilling, 17.
Ethan Crumbley is being charged as an adult, and is facing one count of terrorism, four counts of first-degree murder, seven counts of assaults with intent to murder and 12 counts of possession of a firearm.
The arrest of the parents sends a message about responsible gun ownership.