About 30 people were arrested Sunday outside of a Virginia Marine Corps base in Triangle, Va., during a rally where hundreds protested the treatment of Pfc. Bradley Manning, according to the Associated Press.

Manning, imprisoned for the suspected release of classified material to the WikiLeaks Web site, has been held in solitary confinement at Quantico. He is confined to his cell for all but one hour of the day and is required to strip naked before bed.