Police said Tuesday that they won’t release the name of an officer who shot and killed an unarmed black teenager last week in a St. Louis suburb following threats to the officer’s life, a move that could further inflame protesters who have clashed with authorities while demanding the officer’s arrest.

Ferguson Police Chief Thomas Jackson said Monday the officer’s name would be made public by noon Tuesday. But Officer Timothy Zoll said today that the department will indefinitely postpone the release the shooting officer’s name “for safety purposes.”

“A lot of threats against the officer were made on Twitter, Facebook, all social media,” Zoll said. “We are protecting the officer’s safety by not releasing the name.”

The St. Louis County Police Department, which has been a constant presence in the town since Saturday’s fatal shooting, is also keeping mum.

“We will not ever release the name of the police officer,” said Officer Brian Schellman. “We are investigating the incident, we are investigating the officer, but it is not for us to release the officer’s name. It is a personnel matter. It is up to Ferguson Police.”

The city of almost 21,000 just north of downtown St. Louis has been simmering since 18-year-old Michael Brown was killed in an encounter with police. Circumstances surrounding his death remain contested, but the case has been held up by protesters as an example of police brutality and inequities in the criminal justice system.

On Sunday, the protests boiled over into burning and looting of some local businesses. Monday’s protests were largely peaceful, though police in riot gear fired tear gas and rubber bullets to disperse crowds.

Brown’s family called for peace Monday night during an emotional news conference.

“I just wish I could have been there to help him,” said his mother, Lesley McSpadden.

Tensions remain high Tuesday morning, with more protests planned and dozens of law enforcement officers from across the region stationed in town.

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