While the self-proclaimed Islamic State makes headlines around the globe by executing, torturing and kidnapping thousands of people and threatening attacks world over, US law enforcers consider the terrorist organization a much lesser threat than Americans who call themselves “sovereign citizens” and reject government’s authority over their lives.

A report, released by the Department of Homeland Security this month, claims that those domestic groups have been behind some 24 terrorist acts across the US in the last five years.

The report cites attacks against government buildings and law enforcement by people who reject government authority, such as an incident in 2012 where a routine traffic stop provoked a shootout between the police and father and son in Louisiana. Two police officers were killed. The pair claimed the police, as part of the government, had no authority over them.

Las Vegas Police Department Mug Shot Sovereign Citizens in Las Vegas Police Shooting

In another incident in 2013, a man stating anti-government views shot three Transportation Security Administration employees at the Los Angeles International Airport, killing one. Last year, a couple killed two police officers outside a Las Vegas Walmart.

DHS and FBI officials say “sovereign citizens” believe they can ignore laws and think the government is out to get them. Their activity is not waning, and police are a prime target, officials assert.

“(Sovereign citizen) violence during 2015 will occur most frequently during routine law enforcement encounters at a suspect's home, during enforcement stops and at government offices,” says the report. “Law enforcement officers will remain the primary target of (sovereign citizen) violence over the next year due to their role in physically enforcing laws and regulations.”

Some law enforcement groups say domestic extremism is worse than that of foreign threats such as ISIL, the self-proclaimed Islamic State.

© AP Photo / STR ISIL Flag

A survey by the University of Maryland’s National Consortium for the Study of Terrorism and Responses to Terrorism found that a majority of law enforcement officers listed “sovereign citizen terrorists” as the top threat in the US, ahead of the Islamic State and other terrorist groups abroad.

The Southern Poverty Law Center, which tracks extremists and “hate” groups, estimates there are as many as 300,000 people in the US involved in what the SPLC calls “sovereign citizen extremism.”