As demonstrators flooded the streets of Baton Rouge, La., recently to protest the police killing of a black man there, about 15 men in black military fatigues broke off on their own. They marched toward the police station, three of them carrying AR-15 rifles.

They were members of a group called the People’s New Black Panther Party and they chanted for freedom for black people. They explained that their intent was not to harm police officers but to boldly express their rights to protest and defend themselves.

The broad movement against police abuse that has grown over the past two years has drawn a diverse kaleidoscope of activists who are employing an array of tactics. Among those who are praying, blocking roadways, crying out on social media and negotiating with elected officials are a small but fervent few who are channeling the history of militant resistance in America. They are protesting not just with slogans and signs, but also with rifles slung over their shoulders and a rebellious spirit emanating from their throats.

Micah Johnson, theman who killed five police officers in Dallas, liked two black militant groups on Facebook, but the authorities turned up no evidence that he or Gavin Long, the troubled man who killed three officers in Baton Rouge, was a member of any extremist group. Yet the furor over race and policing appears to have attracted new followers to some seemingly fringe black power groups.

Some activists, while distancing themselves from any calls for violence, argue that the movement is only strengthened by its diversity of strategies. No single group, they say, can steer the movement away from its ultimate goal: To end violence against black people and ensure that they gain control over their lives and communities, after being relegated to second-class status for centuries.

“All of those groups are relevant and important to the struggle for black liberation,” said Cat Brooks, an activist who works closely with the Black Lives Matter network. “We’ve never been liberated, so we don’t know how we’re going to get there. We need all hands on deck.”

The movement has had varying strains from the beginning, as evidenced by the reaction to the August 2014 shooting of Michael Brown in Ferguson, Mo. Peaceful street protests were followed by spontaneous vandalism and looting, which brought widespread attention to the killing and, eventually, deeper problems confronting black communities nationwide.

At rallies, there are widespread cries of outrage against the police, for not valuing black lives, and there are also a few protesters who go further, shouting for the deaths of officers.

In the crop of activist groups that sprang up after Ferguson, one of the earliest to organize was Lost Voices, a collection of young people with a rebellious edge. They shunned organized street protests and instead opted for tactics like crowding into a business and chanting loudly until it had to close its doors. (But they also protected black businesses from being looted.)

“We want to keep an uproar,” said one of the founders who goes by the name Bud Cuzz, adding that he does not condone violence. “We’re not just trying to get on Twitter and take pictures and type in stuff that we think sounds good.”

On Wednesday, the Black Youth Project 100, a national coalition, helped to stage occupations of police unions and departments in cities from New York to Washington to Oakland, Calif. They were aiming to raise awareness of what they say is the complicity of police unions in helping officers to get away with violence.

Brooks, who is based in Oakland, co-founded the Anti Police-Terror Project three years ago to help get black people involved in their communities. The group, for instance, created a commission of community members who investigate police shootings, support families of victims and pressure departments to hold officers accountable.

Yet some fear that the movement against police abuse still has on its periphery some groups with histories of stoking hate.

The Southern Poverty Law Center, which tracks extremist organizations, said it counted 180 groups last year that it considered to be black separatist hate organizations, a 59 percent increase from the previous year.

“What we think has happened is that along with real civil rights groups and movements like Black Lives Matter, black hate groups also profited quite a bit from all of the attention paid to police violence against black men,” said Mark Potok, a senior fellow with the center. “They got a huge boost from Ferguson, Trayvon Martin and the rest.”

The New Black Panther Party and the Black Riders Liberation Party, both of which the Dallas gunman, Johnson, liked on Facebook, are among those that the center considers hate groups.

In describing them as hate organizations, Potok pointed to a Vice News interview from last year with the Riders’ leader in which he repeatedly referred to the police as pigs and said that once the Black Lives Matter movement sees the police’s true intentions, it “will eventually see the need to push for self-defense and revolution.”

He also pointed to a quotation in which a former New Black Panther leader, Malik Zulu Shabazz, suggested killing all Zionists in Israel, including their “old ladies” and “little babies.” And a party leader in Florida put out a $10,000 bounty on the head of George Zimmerman after he was acquitted in 2012 in the killing of Trayvon Martin. Even members of the original Black Panther Party have criticized the new group as hateful and racist.

But Babu Omowale, the national minister of defense for the People’s New Black Panther Party, who said the party’s membership has doubled over the past three years, disputed those characterizations.

On one of its websites, the party said its objectives included uniting all people of African descent, overthrowing white racism and imperialism, and ensuring the educational, cultural and economic advancement of black people.

Omowale conceded that some of the party’s past speech could have been perceived as racist. Khalid Abdul Muhammad, a former Nation of Islam member who took over the New Black Panthers in the mid-1990s, “was hard on white people,” Omowale said.

But Omowale said that two years ago, he and other members created the People’s New Black Panther Party, an offshoot of the New Black Panthers, which gets away from some of the anti-Zionist and black supremacist speech. Instead, he said, they focused mostly on community activism.

“We’re trying to educate people on police terrorism,” he said. “We’re trying to educate people on how the system works.”

He said he considered the party a part of a wider black power movement, not the Black Lives Matter movement. The truth, however, is that the movements are “connected whether they want to be connected or not,” he said. “We’re dealing with the lives of black people who are being murdered around the country unjustifiably by our police departments.”

One crucial difference is that his group advocates armed self-defense, which he said does scare away some people. But the party does not condone violence, he said, and he disavowed the two men who murdered police officers.

“That’s not self-defense,” he said. “That is an offensive position. We’re for self-defense, meaning if someone puts his hands on you, if someone pulls a gun on you and you have the means to protect yourself, then by all means, you protect yourself.”

The civil rights era saw its share of armed resistance, from the Black Panthers to the Deacons of Defense, which acted as self-defense groups, to the smaller, more underground revolutionary proactive violence groups like the Black Liberation Army.

The militancy was born of a history of violence against black people, some African-American academics and activists said, in a country formed by armed rebellion. And with America’s myriad white militias, they said, it would be unfair to single out armed black groups as particularly sinister.

“There isn’t a marginal segment of militant people,” said Ben Ndugga-Kabuye of the Black Alliance for Just Immigration, a pro-immigrant and anti-racism organization. “People are engaged with each other. There’s a fluidity of people across the movement.”