Retired New York Police Department Chief John Chell warned that the possibility of sleeper cells operating in the United States remains a serious concern following the recent attack in Austin, Texas, stressing that both law enforcement and civilians must remain vigilant.
Speaking about the broader security implications of the attack during an appearance on Newsmax TV's "Saturday Agenda," Chell said authorities cannot rule out the presence of dormant extremist networks inside the country.
"It’s a major concern, and there probably are sleeper cells here," Chell said, noting that law enforcement agencies must also contend with individuals who operate independently of larger groups.
He emphasized that so-called "lone wolf" attackers pose a particularly difficult challenge for investigators because they often plan attacks in isolation.
"There are lone wolves that are extremely hard to identify as they plot and scheme what they’re going to do," Chell said.
The FBI has said it’s investigating the Austin shooting as a potential act of terrorism and a law enforcement official told The Associated Press that the gunman was wearing clothes with an Iranian flag design and bearing the words "Property of Allah."
Police have identified the gunman as 53-year-old Ndiaga Diagne and say he legally bought the pistol and rifle that he used in the attack outside Buford’s Backyard Beer Garden.
The venue is on Sixth Street, a nightlife destination filled with bars and music clubs close to the University of Texas at Austin.
According to Chell, major metropolitan areas, particularly New York City, must operate under the assumption that threats are constant, even when officials say there are no specific or credible plots underway.
"When it comes to New York City or any other big city, you always have to be at level ten being the worst," Chell said.
"They say things like, ‘Well, there’s no credible threats.’ As far as New York City is concerned, there’s always a threat."
He added that global events frequently reverberate in major U.S. cities, requiring authorities to remain on heightened alert.
"Anything that happens in this world comes back to major cities and New York City," Chell said. "You have to be at heightened alert at all times."
Beyond law enforcement efforts, Chell said private businesses should also review their security procedures and ensure employees know how to respond during emergencies such as active shooter situations.
"If you’re a large business owner or any kind of company, you should be going over your active shooter plans," he said. "You should be going over your security apparatus."
Chell stressed that preparedness across organizations is critical, adding that employees should be trained on how to react if violence occurs.
"Everyone in that company should know what to do if something happens," he said.
While intelligence sharing between police departments and federal agencies remains a cornerstone of counterterrorism efforts, Chell said the public also plays a vital role in preventing attacks.
"Besides intelligence between police departments and federal partners, there’s one person out there just as important, all the sets of eyes from our civilians," he said.
He urged Americans to remain aware of their surroundings and report suspicious activity to authorities.
"If you see something, you have to say something," Chell said. "Go with your first thought."
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Solange Reyner ✉
Solange Reyner is a writer and editor for Newsmax. She has more than 15 years in the journalism industry reporting and covering news, sports and politics.
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