Missouri Gov. Jay Nixon says law enforcement officials have been working around the clock to make sure residents and businesses will be kept safe once prosecutors announce whether a suburban St. Louis police officer will face charges for fatally shooting 18-year-old Michael Brown.
A grand jury is expected to decide later this month whether to indict Ferguson Officer Darren Wilson in Brown's Aug. 9 death.
Weeks of protests followed the shooting and officials are trying to make sure things remain calm once the grand jury decision is announced.
Nixon says looting and violence that marred mostly peaceful protests cannot be repeated.
He says the state highway patrol will work with St. Louis County and city police as one unified command. The National Guard will also be available if needed.