Experts Skeptical of Brazil Group’s ISIS Pledge Before Olympics

— -- Experts are questioning a recent pledge of allegiance to ISIS by a purported group of extremists in Brazil in what may be an attempt to rattle the international community before the Rio Olympics.

A group calling itself Ansar al-Khilafah Brazil on Sunday pledged its loyalty to ISIS leader Abu Bakr al-Baghdadi on the messaging app Telegram and promised to “wage jihad against the enemy of Allah.” The group also posted ISIS propaganda translated into Portuguese.

But J.M. Berger, a terrorism expert who closely follows ISIS’ online activity, said he doubts Ansar al-Khilafah Brazil actually exists.

“The Ansar al-Khilafah Brazil Telegram channel appears to be the work of an ISIS social media activist rather than reflecting any bricks-and-mortar initiative,” said Berger, a co-author of “ISIS: State of Terror.”

John Horgan, an ISIS expert who teaches at Georgia State University, said he didn’t know if the group was real, but he called ISIS supporters “masters of exploiting opportunity,” such as security concerns over the Olympics.

A U.S. counterterrorism official told ABC News, however, that while ISIS isn’t known to have any cells in Rio de Janeiro, “we should take every threat like this seriously.”

ISIS is not believed to wield much influence in Brazil, where a tiny percentage of residents are Muslims, much less Islamic extremists. Only three individuals are said to have traveled from Brazil to Syria and Iraq to fight with any extremist groups, according to the Soufan Group, compared with an estimated 1,700 from France and 250 from the U.S.

In a recent interview, a former counterterrorism official told ABC News that at least as of last month, there was “no credible ISIS-related threat to the 2016 games.”

“It’s not impossible, but ISIS has other areas in the world where it is much easier for them to operate,” the former official said, a sentiment shared by Horgan.

Matt Olsen, a former director of the National Counterterrorism Center, said that historically Islamic terrorist groups like al-Qaeda have made “limited inroads” in South America but that any sign that the jihadist extremist threat has grown on the continent “would be concerning.”

The U.S. State Department’s Overseas Advisory Council, which offers guidance to American companies on security issues, noted a litany of security concerns at the Rio Olympics in a May report obtained by ABC News, from local protests to the Zika virus. But the report did not mention any terrorist threats.

Still, as the Olympics are set to begin next month and ISIS-inspired terrorist attacks repeatedly claim innocent lives the world over, intelligence officials in Brazil reportedly consider the terrorism threat high.

Last month the chairman of Brazil’s joint chiefs of staff told Reuters that after terrorist attacks in Paris and Brussels, “a bell went off in terms of terrorism.”

Today an unidentified purported Islamic extremist also used Telegram to call for attacks on the Olympics and listed suggestions for lone-wolf attacks and targets.

The State Department Bureau of Diplomatic Security, which has responsibility for the security of American Olympians and spectators, declined to comment for this report, describing the threat from the purported Brazilian group as an “intelligence matter.”