Dallas Area Rapid Transit Cpl. Gary Hutchinson salutes the funeral procession for Dallas police Sgt. Michael Smith on Interstate 20 in Duncanville, Tex., on Wednesday. Smith and four other officers were killed in an attack during a peaceful Black Lives Matter protest. (Nathan Hunsinger/Dallas Morning News via AP)

Three first responders in South Carolina have been fired for insensitive posts on social media, two days after a Columbia fire captain was dismissed over a Facebook post in which he threatened to run over protesters blocking traffic — part of a wave of public employees who have been lashing out online as protests roil the nation.

Columbia Fire Chief Aubrey Jenkins told local TV station WLTX that senior firefighter Dave W. Proctor, who had been part of the department since 2013, and probationary firefighter Edward Augustyn III, who was hired in February, were dismissed for writing “unprofessional [comments] and/or threats on social media” about protesters.

It’s not clear what those comments were, since they have been deleted. But a Columbia Fire Department spokesman told the Associated Press that the men were fired as part of the same investigation that led to the dismissal of Capt. Jimmy Morris, a 16-year veteran of the department, on Monday. Morris had reportedly written on Facebook: “idiots shutting down I-126. Better not be there when I get off work or there is going to be some run over dumb a—.”

The Black Lives Matter protest, which blocked part of the interstate Sunday night, was legally sanctioned.

Also on Wednesday, officials in Richland County, which includes the city of Columbia, announced the dismissal of a senior paramedic who made “inappropriate comments” online.

“EMS is called upon to serve citizens in times of duress,” interim county administrator Gerald Seals said in a statement. “The statements on social media were threatening and could be taken as the County having individuals, who because of their bias, may adjust their care – and that erodes public trust and is unacceptable.”

Other Richland County employees were also being investigated for online comments, according to a news release from the county. It did not elaborate on the content of those comments or when they were posted.

The dismissals come at a time of heightened tensions between demonstrators and public officials. In the past week, protests have erupted in Columbia and around the county in response to the killings of two black men by police and an attack that left five police officers dead in Dallas.

The South Carolina first responders are among at least a dozen public employees who have lashed out against protesters on social media and been punished for it. On Monday, a Michigan police detective was demoted after calling Black Lives Matter protesters “terrorists” on Facebook. A cop in Overland Park, Kan., was fired for a threatening comment he posted on a black woman’s Facebook photo of her daughter. “We’ll see how much her life matters soon,” he wrote, “Better be careful leaving your info open where she can be found :) hold her close tonight, it’ll be the last time.”

Police officers in Memphis have been suspended over a Snapchat post showing someone pointing a gun down a hallway at a cartoon of a black man running; according to the Bradenton (Tenn.) Herald, the image was posted the night the Dallas officers were killed.

And on Sunday, the Fort Worth Police Officers Association, which represents about 1,500 officers and officials in Dallas’s closest neighbor, wrote on Facebook that Black Lives Matter “chooses to MURDER American law enforcement officers,” according to the Dallas Morning News. The page also shared a screenshot from an unverified Facebook account called “Black Lives Matter Dallas Texas Chapter” that called the shooting of the Dallas officers “justified.” The image appeared to be fake, but it went viral before the group took it down.

Black Lives Matter leaders have condemned the killing of police in Dallas and have called for protesters to remain nonviolent.

Both of the Fort Worth Police Officers Association posts were later deleted, “as we simply wanted unity in our communities,” the association’s communications director, officer Anthony White, told the Morning News. But he remained critical of the Black Lives Matter movement.

“As an association that represents police officers, we will not support a business or organization that has shown to conduct and/or support violent acts toward those who wear a uniform and serve our communities,” he said.

Read more:

Why police in Baton Rouge look like they’re dressed for war

As arrests mount in Baton Rouge, protesters question police tactics

‘I’m under arrest, y’all’: Black Lives Matter activist arrested, then released in Baton Rouge

‘Super-fishy’: Man who posted video of Alton Sterling killing claims he was targeted by vengeful police

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