Attorneys for the officials that oversaw the grand jury investigation after Michael Brown’s death, have asked a federal judge to withhold the “grisly” photos of the 18-year-old’s body, saying they’re worried they could prompt violence if leaked.

The St. Louis County police and prosecutor made that request in a court filing, earlier this week, related to a wrongful-death lawsuit by Brown’s family. The filing warned that if the images became public they “may provoke unbridled violence.”

Brown’s death prompted protests, sometimes violent clashes with police and helped create the Black Lives Matter movement.