Minneapolis Police Chief Janeé Harteau issued a stern public warning Thursday that protesters who interfere with public safety will be arrested, as activists await a decision any day on whether two officers will be charged in the shooting of Jamar Clark.

Meanwhile at 10 a.m. Friday, a joint news conference by the Minneapolis NAACP, the Twin Cities Coalition 4 Justice 4 Jamar, Black Lives Matter Minneapolis and Black Clergy United for Change will discuss the pending decision.

Harteau issued the message months after demonstrations that roiled the city's North Side for weeks after Clark's death last November. While the ensuing 18-day occupation of a police station several blocks from where he was killed was mostly peaceful, a few protesters hurled Molotov cocktails and rocks, and scrawled anti-police messages on the side of the building. Those scenes were shown in a video the department posted online along with Harteau's statement.

"We will not allow people to set fires on our streets or occupy and vandalize our buildings," Harteau said. "We will not allow people to jeopardize the safety of others by causing massive disruptions and hindering emergency vehicles from helping those in need."

Some of the protest organizers criticized Harteau and the department for what they called a heavy-handed response that saw some officers using batons and pepper spray against protesters.

More protests are expected next week if Hennepin County Attorney Mike Freeman decides not to charge the two officers, Mark Ringgenberg and Dustin Schwarze, with Clark's death.

Harteau warned that while the department respects free speech rights of likely protesters, it won't come at the cost of public safety. She added that officers will decide how to handle any actions by protesters on a case-by-case basis.

"For every person who wants to protest or deliver a message in the streets, there's someone else who's just trying to get home," she said at a Thursday afternoon news conference at City Hall. She told reporters that the department had considered several options to deter potentially inflammatory protests, including instituting a curfew.

Officers in the Criminal Investigations Bureau were told in an e-mail this week to bring their uniforms to work, with the expectation that they could be pressed into service, said Lt. Bob Kroll, head of the police union.

Harteau's announcement was almost immediately met with criticism on social media and from community activists who have led the protest.

"It's not the community's character that's been in question, it's the Minneapolis Police Department's that's in question," said Mel Reeves of the Twin Cities Coalition for Justice 4 Jamar, which held weekly protests at Freeman's office. "She sent a not-so-subtle message that a decision has already been made."

Reeves said that the timing of the announcement appeared intended in part to dissuade people from attending a rally outside the Hennepin County Government Center on Saturday.

Several protest groups said that the police plan would not deter further protests if Freeman decides against indicting the officers. Justice 4 Jamar called on people to flood the phone lines of the county attorney's office and that of Hennepin County Commissioner Jan Callison, demanding prosecution of the officers.

The announcement came a week after Freeman's decision to forgo the grand jury in all police-involved shootings, a long-standing practice that had been criticized recently for its lack of transparency.

Freeman had resisted past calls to do away with the grand jury system, including notably in the case of Tycel Nelson, another unarmed black man who was killed by police in Minneapolis in the early 1990s.

Freeman said that he and several of his prosecutors would investigate and determine whether any charges are warranted in the shooting of Clark, which occurred during a scuffle with the two officers.

The police union has said Clark had his hand on one of the officers' guns when he was shot.

Witnesses say that's not true and that Clark was handcuffed at the time.

At the time of the precinct occupation, some officers privately accused the administration of bowing to pressure from anti-police protesters in not ending the occupation sooner. Harteau said on Thursday that factored into her decision.

Freeman said he intends to stick with his original deadline of reaching his decision by the end of March.

In February, the U.S. Department of Justice, at the behest of local officials, announced that it would conduct an investigation into the city's handling of the Fourth Precinct occupation, much as it did after the angry protests that followed the death of Michael Brown in Ferguson, Mo. The "after-action review" by the department's Community Oriented Policing Services (COPS) office is expected to last at least until this fall.