Baltimore State's Attorney Marilyn Mosby announced that all six officers charged in the death of Freddie Gray were indicted by a grand jury. Mosby is pictured here May 1, 2015. Reuters/Adrees Latif

A Maryland grand jury has indicted all six officers charged in the death of Freddie Gray, a Baltimore resident who died of a severe spinal cord injury allegedly sustained while in police custody. The officers are now scheduled to be arraigned on July 2, said State's Attorney Marilyn Mosby, who announced the indictments in a news conference on Thursday.

Gray’s death last month sparked mass protests and riots in Baltimore, along with demonstrations across the country. The 25-year-old African-American man was arrested by Baltimore police on April 12 and allegedly suffered a spinal injury in the hour before his arrival at a police booking station. He went into a coma several days later and died a week after his arrest, prompting an investigation into the circumstances of his detention.

The medical examiner’s office ruled Gray’s death a homicide caused by severe trauma on May 1, the same day that Mosby announced her office had found probable cause to pursue criminal charges against the officers. Officers Caesar Goodson Jr., William Porter, Edward Nero and Garrett Miller, Lt. Brian Rice, and Sgt. Alicia Miller were subsequently arrested, with charges ranging from false imprisonment to second-degree depraved heart murder. The officers have maintained their innocence, with an attorney for one of the accused arguing that they would be vindicated because they had “done nothing wrong.”

The investigation by Mosby’s office found that officers ignored Gray’s pleas for help. They also bound Gray’s arms behind his back and put cuffs on his legs before loading him on his stomach into a police wagon, she said. Mosby also said the police had not secured Gray with a seat belt, contrary to the police department’s regulations.

Mosby has been under great pressure from the police union and officers for her handling of the case, with the Baltimore City Fraternal Order of Police calling for Mosby to step down and appoint a special independent prosecutor instead.