Police officers stand in position as they watch demonstrators protest Michael Brown's murder August 16, 2014 in Ferguson, Missouri. Missouri Governor Jay Nixon and Missouri State Highway Patrol Captain Ronald Johnson imposed a 12am curfew for demonstrators continuing to protest the the killing of Brown, who was shot and killed last week by Ferguson Police Officer Darren Wilson after being suspected in taking part in a robbery at a convenience store. Joshua LOTT/AFP/Getty Images

Update 9:30 p.m.: St. Louis County Prosecutor Bob McCulloch Saturday announced plans to convene a grand jury this week to examine the Michael Brown case. “We’re going to start presenting everything to the grand jury as quickly as we can,’’ McCulloch told St. Louis Public Radio. “We’re not going to wait until we have everything, and then do it." The prosecutor urged anyone with information to come forward.

Original post:

Missouri Gov. Jay Nixon Saturday declared a state of emergency as the protests related to the shooting of Michael Brown turned violent and destructive on Friday night. The state of emergency imposes a curfew from midnight to 5 a.m.

Authorities hope the curfew will curtail some of the looting, but protest leaders have expressed concern it is too early and will lead to clashes because protesters will be asked to disperse before they are ready. Captain Ron Johnson of the Missouri State Highway Patrol, which has taken over peacekeeping duties in Ferguson, said his department will enforce the curfew with words, not with tear gas or rubber bullets. Johnson has become a face for his department’s restrained response efforts, a stark contrast to the militarized Ferguson and St. Louis Police Department response that President Obama called “excessive.”

Members of a group named the New Black Panther Party (no affiliation with the original Black Panther Party) worked last night to maintain calm within the ranks of protesters, but eventually some demonstrations turned violent. Some store owners said the police weren’t doing enough to protect property from looters and some took it upon themselves to protect their stores. Groups of protesters also stood guard at storefronts to prevent looting.

Demonstrators attempt to stop masked individuals from entering a store that had been broken into, during on-going demonstrations to protest against the shooting of Michael Brown, in Ferguson, Missouri, August 16, 2014. Protesters in Ferguson said late on Friday on Twitter that police had fired tear gas at a crowd protesting over the police shooting death of Brown, an unarmed black teen. The reported outbreak late Friday evening came after almost a week of nighttime clashes between local police and protesters saw a 24-hour break as those police forces were replaced by state police led by an African-American captain. REUTERS/Lucas Jackson

After days of complaints, the Ferguson Police Department released the name of the officer, Darren Wilson, who shot and killed Michael Brown last Saturday and a packet of information linking Brown to a convenience store robbery earlier that day. Critics argue the police department was attempting to turn attention away from the shooting and discredit Brown, something that could have played into the violence on Friday night. The Justice Department disagreed with the decision to release video of the robbery for fear “it would roil the community further.”

The Rev. Al Sharpton criticized looters, saying “to become violent in Michael Brown’s name is to betray the gentle giant that he was.”