Ali Velshi knew almost instantly what had happened when he felt a sharp pain in his leg Saturday night in Minneapolis: He’d been hit with a rubber bullet fired by police.

“As a kid growing up in Canada, it felt familiar. It felt like a puck hit me in the shin,” said the MSNBC anchor, who was covering what he described as a peaceful march of protesters. “It hit in a place that hurt.”

Velshi, who suffered minor bruises, was one of at least a dozen journalists injured in cities across America this weekend — including a photographer who was blinded in one eye — as police fired rubber bullets, pepper spray and tear gas to quell unrest. Not since the 1960s, when the nation was racked by civil rights demonstrations, antiwar protests and urban riots, has the press been embroiled in so much violence on American shores.

In several cases, reporters appear to have been swept up in indiscriminate efforts by authorities to disperse crowds. But in a number of incidents, journalists were injured, harassed or arrested even after identifying themselves as reporters — a blatant violation of constitutional protections and long-standing ground rules that guide interactions between media and law enforcement officials.

Later on Saturday, for example, Velshi said his and another TV crew were confronted by police in a nearly deserted parking lot and informed them they were news media. “ ‘We don’t care,’ ” Velshi said the police told him before opening fire, without injury.

Elsewhere around the world, journalists are regularly arrested or injured covering demonstrations as governments attempt to suppress reporting that threatens their legitimacy. But such examples have been rare in the United States. Before the Minnesota protests, only 43 journalists here over the past three years had been detained by police while covering demonstrations — 37 of them during protests over President Trump’s 2017 inauguration, according to Joel Simon, executive director of the Committee to Protect Journalists.

Whether these assaults are happening by accident or on purpose, they have the effect of impeding the news — hampering the public’s ability to see and judge the behavior of officials who are accountable to them. They may also amount to an infringement of human rights.

Simon sees several troubling forces behind the deteriorating dynamic between police and reporters. Police departments are increasingly relying on “quasi-military” tactics to suppress demonstrations — such as “kettling,” in which two lines of officers bottle up protesters in a confined space and arrest everyone caught in between, including reporters.

And unfortunately, in many communities these days, where economic pressures have forced media layoffs and cutbacks in coverage, “the police simply don’t know the journalists who are covering them,” Simon said.

Meanwhile, social media has undermined public trust in the news media, a phenomenon fueled by Trump’s frequent criticism of the press. Which makes it more likely that reporters will be met with hostility by police or demonstrators.

“I’ve never seen anything quite like this,” Simon said. “Many of the norms have broken down.”

In some cases this weekend, it was protesters who targeted journalists: A Fox News crew was punched and harassed outside the White House early Saturday; a crowd defaced the facade of CNN headquarters in Atlanta.

But much of what has transpired against reporters was perpetrated by police.

CNN cameraman Leonel Mendez and producer Bill Kirkos were both hit by rubber bullets as they were covering the street protests in Minneapolis Saturday evening, suffering minor injuries. A day earlier, Mendez and Kirkos were arrested along with correspondent Omar Jimenez in an incident carried live on the network.

Vice News reporter Michael Anthony Adams shouted nearly a dozen times that he was a member of the media as police in Minneapolis poured out of a van and yelled for people to leave.

“I don’t care,” said one officer, ordering Adams to the ground. As Adams lay facedown, showing his press badge, he was hit by a blast of pepper spray. The exchange was caught on camera.

Several of the most chilling accounts came from Minneapolis, where the national protests first erupted last week after the death of an African American man, George Floyd, after a white city police officer arresting him knelt on his neck for more than eight minutes.

Los Angeles Times reporter Molly Hennessy-Fiske wrote that several journalists in Minneapolis shouted “press” and waved credentials but were nonetheless cornered and chased by police spraying tear gas and firing rubber bullets. One hit her photographer colleague, Carolyn Cole, in the face.

“I didn’t realize it, but I was bleeding from several wounds to my leg,” Hennessy-Fiske wrote. “Blood covered the face mask of a reporter next to me, who was so stunned someone had to tell him he was hurt.”

Reuters TV cameraman Julio-Cesar Chavez was filming police about 8 p.m. Saturday when they began firing. “I’ve been hit in the face by a rubber bullet!” he said on camera. Chavez was hit in the back of his neck, under his left eye and his arm, while a Reuters security adviser also suffered injuries, according to the wire service.

Journalists weren’t even safe in their cars. Minneapolis Star Tribune reporter Ryan Faircloth had blood running down his face as he said on camera that he was “just trying to get out of the area” when a police tear-gas round shattered a car window. He was hit in the face and arm.

In some parts of the country, police detained journalists, including HuffPost reporter Christopher Mathias, who wore a press badge while on assignment to cover protests in Brooklyn. He was released several hours later.

In Michigan, Detroit Free Press senior news director Jim Schaefer said on Twitter that several of his reporters were pepper-sprayed by police, and an officer slapped a live-stream camera out of the hand of a photographer “as she tried to do her job. This is not OK.” Free Press reporter J.C. Reindl captured a chilling image of a police officer wearing a gas mask just an arm’s-length away. “Last thing I saw before I got sprayed,” he tweeted. “I was even holding up ‘media’ badge.”

“One of the craziest nights of my career. Got tear gassed multiple times,” tweeted Free Press reporter David Jesse. “Police shot rubber bullets at us even [though] we were moving where they wanted us to go, holding up our press passes and yelling media.”

Police representatives in Minneapolis and Detroit did not respond to requests for comment on Sunday.

An officer in Louisville on Friday night pointed a gun containing pepper balls at a local TV news cameraman as reporter Kaitlin Rust screamed on live TV, “I’m getting shot!” An anchor back in the studio asked who the officers were targeting. “At us! Directly at us!” she replied.

Louisville police spokeswoman Jessie Halladay said the department was trying to identify the officer who fired at them. “Targeting the media is not our intention. There was a lot going on last night, and to be fair to both the officer and to Kaitlin, we need to take a deeper look at what happened and what prompted that action,” Halladay said in a statement, according to the station. “So we have said that we will do that and if there needs to be discipline we will address it.”

In Los Angeles, KCRW journalist Cerise Castle tweeted a photo of the rubber bullets that she said police fired at her and protesters. One of them hit her.

Hennessy-Fiske, the Los Angeles Times reporter, wrote that what she experienced in Minneapolis was unlike anything she’s experienced in a career that has taken her to war zones in Iraq and Afghanistan and protests in cities like Ferguson, Mo., and Dallas.

“I have never been fired at by police,” she wrote Saturday, “until tonight.”

This story originally published at 12 p.m. Sunday and has been updated.