Attorneys for the police force and prosecutor that oversaw the investigation of Michael Brown’s 2014 death in Ferguson asked a federal judge to consider blocking the release of “grisly” photographs of the black 18-year-old’s body to his family’s attorneys, worried they could prompt violence if leaked.

The St. Louis County counselor’s office filed the request Tuesday with a federal judge presiding over the wrongful-death lawsuit filed by Brown’s parents. U.S. District Judge E. Richard Webber had rejected a separate request by Brown’s mother to broaden who can see sensitive grand jury details related to her son’s death earlier that day.

An attorney for the county’s prosecutor and police department said the photographs of Brown dead on the street, during his autopsy and in the morgue could rekindle the violence that accompanied protests of Brown’s death.

“These particular grisly images evoke a visceral reaction which may provoke unbridled violence,” Linda Wasserman wrote in that motion, which asked Webber to first privately vet the photographs. “The disturbing impact of the photographic images could cause the simmering cauldron of emotions associated with this matter to quickly reach the boiling point.”

Wasserman added that “a wrongdoer” given access to the photographs easily could make a duplicate of them “in an anonymous and clandestine fashion, making it difficult, if not impossible, to trace the illegal disclosure.”

Anthony Gray, an attorney for Brown’s family, declined on Wednesday to discuss Wasserman’s filing or concerns, telling The Associated Press that “I’m going to be totally deferential to the court on this one.”

Webber had agreed in June to let no more than two attorneys for each of Brown’s parents and for the defense see testimony and the names of witnesses from the secret St. Louis County proceedings involving Brown’s death.

That grand jury declined to indict Darren Wilson, the white Ferguson police officer who shot and killed Brown, who was black and unarmed, during an August 2014 confrontation on a street.

Brown’s death and the grand jury’s decision led to sometimes-violent protests in Ferguson and helped propel the Black Lives Matter movement, which criticizes police treatment of minorities.