DeRay Mckesson, the Baltimore-born activist and one of the faces of the Black Lives Matter movement, has a new T-shirt for sale: simply, the words "Black Identity Extremist" in white letters on a black background within a white box.

It is mocking, for sure, the FBI's report — released in August and obtained by Foreign Policy magazine last week — that newly classifies "Black Identity Extremists" as a growing terror threat against law enforcement. BIEs, the report says, are individuals who seek retribution through violence for "perceived racism and injustice in American society."

But to Mckesson, the $28 T-shirt (and $40 hoodie) claim the terminology triumphantly. On the site that sells the merch, he writes: This is confirmation that the work of social justice continues to threaten those in power.

"It's not new for the government to target activists, especially black activists," Mckesson said in a telephone interview. "We are only threats if you think that equity and justice are threats."

Experts, too, who are familiar with counterterrorism policies, warned the terminology was invented in an effort to give law enforcement license for bias.

"It's a made-up term," said Michael German, who spent 16 years undercover in the FBI with neo-Nazi groups and now works with the Brennan Center for Justice at New York University School of Law. "There is no such thing as a Black Identity Extremist movement."

"The bureau may once again be profiling black activists because of their beliefs and race, not because they pose a real threat of violence," said Nusrat J. Choudhury, senior staff attorney for the American Civil Liberties Union's racial justice program, calling the report "seriously flawed in its conclusions and methodology."

Incorrectly identifying protesters as extremists can be dangerous for police as well as civilians, leading to misdirected resources and a biased law-enforcement response, German said.

The terminology was created "in an ill-advised attempt to create parity to serve as the opposite side of the coin to white supremacists," he said.

The report was, in fact, dated Aug. 3, only days before a group of white supremacists and neo-Nazis gathered in Charlottesville, Va., for a rally that resulted in the death of Heather Heyer, a white woman, killed after a white man from Ohio plowed his car into a crowd of counterprotesters. Two law enforcement officers also were  killed in a helicopter crash while monitoring the rally.

The FBI's public affairs office in Washington said Tuesday that it could not comment on specific questions about the report. But it issued a statement:

"The FBI investigates activity which may constitute a federal crime or pose a threat to national security and cannot initiate an investigation based solely on an individual's race, ethnicity, national origin, religion, or the exercise of First Amendment rights.

"The FBI remains committed to protecting those rights for all Americans. Our focus is not on membership in particular groups but on individuals who commit violence and other criminal acts. Furthermore, the FBI does not and will not police ideology. When an individual takes violent action based on belief or ideology and breaks the law, the FBI will enforce the rule of law."

The FBI report cited six individual cases where men were motivated to violence because of "alleged" police brutality. They had no connection to each other or the Black Lives Matter movement.

"The only thing they have in common is that they're black," German said.

Micah Johnson, who ambushed and killed five officers in Dallas during a protest against police shootings last July, had "searched and liked social media pages of BIE and black separatist groups," and had been ousted from a local BIE group for being too radical, the report cited.

It also noted the five officers were white. However, one of the officers, Patricio "Patrick" Zamarripa was Mexican-American, according to his obituary and news reports.

The FBI did not respond to a question about its description of Zamarripa's ethnicity.

Gavin Eugene Long ambushed and shot six law enforcement officers, killing three, in Baton Rouge, La., also last July. The report noted that Long, a Moor, had expressed "frustrations with the police and criminal justice system."

But Moorish sovereign citizens are a network of mostly African Americans who do not recognize the authority of the U.S. government.

Choudhury, of the ACLU, said the FBI simply linked together black men who had varying ideological beliefs.

"The report itself acknowledges that the six violent incidents it looks at appears to have been influenced by more than one ideological perspective," she said.

The  NAACP used the FBI report to urge its members to take action.

"It's time for us to stop the true sources of  hate in this country," said Derrick Johnson, interim president and CEO.

He urged NAACP members to call Congress in support of the No Hate Act, a Senate bill that would provide incentives for hate-crime reporting, grants for state-run hate-crime hotlines, and additional penalties for individuals convicted under the Matthew Shepard and James Byrd Jr. Hate Crimes Prevention Act.

"In a time when white supremacists are marching down city streets with loaded weapons and tiki torches – organizing rallies of terror around the country—it comes as a great shock that the FBI would decide to target black identity groups protesting police brutality and their right to exist free of harm as a threat," Johnson said.

While the report doesn't name Black Lives Matter, its history of the BIE movement mirrors that of Black Lives Matter, and it cites 2014 — the year Black Lives Matter protests erupted after Michael Brown in Ferguson, Mo., was killed by a police officer — as the year there was a spike in BIEs targeting law enforcement.

According to German, the FBI has issued warnings in the past about violence from black separatists. Even still, black separatist movements are minuscule when compared to white separatists movements, he said.

"There is no parallel black supremacist movements in the United States that has a coherent ideology and organization that would somehow mirror the white supremacy movement that has been extremely organized and violent over the last 150 years," he said.