Authorities Warn of Potential Fourth of July Terror Attacks

Johnson says people should attend Independence Day events as planned but "remain vigilant" and report any suspicious activity.

He says U.S. authorities will adjust security measures, including those unseen by the public, as necessary.

On  Sunday, House Homeland Security Chairman Mike McCaul said Americans should heed the government's warning.

"It is concerning," McCaul told "Fox News Sunday." There is a great deal of chatter, a high volume," he said of terrorist network communications.

He noted that a spokesman for the Islamic State (ISIS) has called for jihad during the Islamic holy month of Ramadan — currently under way — the one-year anniversary of the establishment of the ISIS caliphate and the American Independence Day holiday.

In addition to that confluence is the "Bloody Friday" attacks in France, Tunisia and Kuwait, all within hours of each other, in which ISIS claimed credit.

The warning to Americans was issued jointly by the FBI, the Department of Homeland Security and the National Counterterrorism Center.

"I think given these confluence of events we're being on the cautious side here to warn the public to remain vigilant," McCaul said, "to enjoy the Fourth of July parades, but remain vigilant during these celebrations."

Foiled terror plots have increased "exponentially" in the past year, McCaul said, because of Internet recruiting.

"I'm extremely concerned about the way the Syrian ISIS recruiters can use the Internet at lightning speed to recruit followers in the United States, with thousands of followers in the United States," he said, "And then activate them to do whatever they want to do, whether it's military installations, law enforcement or, possibly, a Fourth of July event parade."

A gunman killed at least 37 people and wounded 36 in an attack on a beach resort in Tunisia Friday. In Kuwait, a suicide bomber killed at least 25 people, while a man with suspected ties to French Islamic radicals rammed a car into a gas factory in southeastern France, triggering an explosion that injured two people. The severed head of a local businessman was left hanging at the factory's entrance.

While there was no specific or credible threat of attack, one law enforcement official told USA Today that a new intelligence bulletin is alerting local colleagues to the ongoing threats posed by the group that calls itself the Islamic State [also known as ISIS or ISIL] and other homegrown extremists. The official was not authorized to comment publicly.

The bulletins are frequently issued in advance of major U.S. holidays out of an abundance of caution and concern that operatives may exploit the timing to generate greater attention.

The FBI and other agencies have worked to disrupt a number of Islamic State-inspired plots, including a planned assault earlier this month on police officers in Boston. In that case, authorities fatally shot Usaamah Rahim as he allegedly planned to attack police with military-style knives.

Earlier this month, a New York suspect in an Islamic State-related terror investigation was arrested after attacking an FBI agent with a kitchen knife during a search of his home. Fareed Mumuni, 21, was charged with attempted murder, after he emerged as a suspect in alleged plots to use pressure-cooker explosives and knives to attack police.

"Particularly with the upcoming July Fourth holiday, here in the United States the Department of Homeland Security and the FBI continue to communicate with state and local law enforcement about what we know and see," Johnson said Friday. "We are encouraging all law enforcement to be vigilant and prepared."

Johnson said that "all Americans" should continue to "attend public events and celebrate."

Friday's attacks that spanned three continents are leading U.S. intelligence agencies to reconsider an earlier opinion that the Islamic State is mostly a "regional threat."

The National Counterterrorism Center and the CIA are working together to determine if the murders were coordinated by ISIS leaders or carried out by "lone wolves" in the name of the militant group, reports Politico.

But either way, the attacks will likely change how the United States and the Obama administration deals with the ISIS attacks in three countries on Friday, which officials suspect may have been directed — or at least heavily influenced — by the militant group.
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Earlier this year, Director of National Intelligence James Clapper told Congress that ISIS was a regional threat that would probably only conduct operations in the Middle East, and Joint Chiefs of Staff Chairman Gen. Martin Dempsey called ISIS "an internal conflict, internal to Islam."

But ISIS is becoming a global threat because of its ability to "evangelize followers, retired Army Col. Peter Mansoor, who helped create the U.S. military campaign against al-Qaida.

"This will only continue unless something is done to destroy ISIL and reduce its appeal to the extremist fringe in the Islamic community," he commented.

The timing of the attacks was not coincidental, said California Republican Rep. Ed Royce, who chairs the House Foreign Affairs Committee.

The day of attacks were launched after ISIS pushed followers to "rush and go to make Ramadan a month of disasters for the infidels," leading to fears of attacks during the Muslim holy month that started on June 17. The "bloody Friday" also came just days before ISIS will celebrate its first anniversary of when its leaders declared intentions to establish a caliphate in its controlled territories.

"These attacks show that the [ISIL] threat is spreading well beyond Iraq and Syria," Royce told Politico. "A continued safe-haven there means more attacks across the region, Europe and even here at home."

Royce called for more targeted airstrikes, as well as finding a way to destroy ISIS' ability to target young people online and sending a counter message that "ISIS offers no peace, no community, and no future."

Counterterrorism experts says ISIS may not need to exercise much coordination pull off such attacks, as the terror group's leaders can simply use social media to make a general call for worldwide attacks.

"We do know that ISIL encourages lone wolf attacks," Air Force Col. Pat Ryder, spokesman for the U.S. Central Command, responsible for the Middle East, told reporters at the Pentagon this week."They urged their regional affiliates to conduct attacks against Western and coalition interests and Shia population centers, but it’s really too early to tell whether they were involved in these attacks."

ISIS may also be moving away from al Qaida's method of waging large attacks, such as the Sept. 11 events, Western officials fear, meaning that the attacks could come more frequently, but with less warning.

The attacks came a day after House Intelligence Chairman Mike McCaul, R-Texas, citing ISIS, proposed legislation to create a special office on the Department of Homeland Security to counter the spread of violent extremism.

"We have arrested more people in the United States this year who have been inspired by [ISIS] than there are officials working to keep [the group] from radicalizing Americans," McCaul said.

The Texas Republican has proposed legislation to create a special Department of Homeland Security office to counter violent extremism.

"Terrorists at home and overseas are bringing the battle into our homes through the internet," he said. "We cannot afford to complacently watch the threats mushroom. It is time for action, and to treat this issue like the priority that it is."