Two former security guards have been indicted by a grand jury for involuntary manslaughter in the death of a hospital patient in Washington.

The medical examiner's office said 74-year-old James McBride died of "blunt force injuries" of the neck, including damage to his spinal cord. McBride's death was ruled a homicide.

MedStar Washington Hospital Center officials previously said McBride was a patient at the hospital when he left Sept. 29 without being formally discharged. Officials said McBride was being escorted back to the hospital by the security guards when an altercation occurred.

Prosecutors say 30-year-old Clifton Montgomery of Bladensburg, Maryland, and 43-year-old Charles Brown of Fort Washington, Maryland, were indicted Tuesday.

The hospital says the guards haven't worked there since November.