The US Department of Justice won't bring federal charges against six Baltimore police officers involved in the 2015 arrest and death of Freddie Gray. The African-American man's death in police custody prompted weeks of protests.

Gray, 25, died from a severe spinal injury in April 2015, after being arrested for having a switchblade and running away from police. He was loaded into a police van without a seat belt, while wearing handcuffs and shackles. The medical examiner found his spinal cord had been severed and ruled his death a homicide.

Federal officials have been looking into the case, to see whether Gray’s civil rights were violated during the arrest.

Attorney for the officers in question said the officers were charged with 'violations of policy and procedure' https://t.co/Yr6HSlCH3M — RT America (@RT_America) May 22, 2017

Billy Murphy, attorney for Gray's family, said the Justice Department informed him on Tuesday that no charges will be filed.

The six Baltimore PD police officers faced state criminal charges, including manslaughter and second-degree murder. After one mistrial and two acquittals, state attorney Marilyn Mosby dropped all the charges. The officers still face an internal disciplinary trial, which begins October 30.

“We know that spines do not break without cause, and the DOJ and the BPD’s credibility to make change a reality in Baltimore hinges not just on their ability to institute much needed reforms to police training, policies, and practices, but also on their success in bringing to justice officers who abuse their power and take the lives of innocent residents,” Sherrilyn Ifill, president of NAACP’s legal defense fund, told the Baltimore Sun. “The onus is now on the BPD to hold these officers accountable at their disciplinary trials this fall and winter. Baltimore will be watching.”

A 2015 DOJ investigation of the Baltimore PD found the police was conducting unconstitutional stops, searches and arrests disproportionately targeting African-Americans, using excessive force, and retaliating against individuals for engaging in constitutionally-protected expression. The city and the DOJ reached a settlement on police reform in January.

In April, US Attorney General Jeff Sessions requested a delay in implementing the police reform plan, but a federal judge rejected that request.