A group of at least five self-proclaimed "sovereign citizens" moved into an empty Maryland mansion and tried to claim it as their own, the Baltimore Sun reported Thursday.

The group, which included a dentist and a convicted sex offender, moved in, changed the locks, and put a chain across the driveway with a "private property" sign.

The homeowner, who did not want to be named due to safety concerns, had moved out of the $1.5 million home in Baltimore County and listed it for sale after the death of her husband last year. When a neighbor noticed unusual activity, including people unloading furniture, she notified the homeowner.

The homeowner then realized she was being sued for property ownership. Police reports reviewed by the Baltimore Sun said one of the people called the takeover a "sovereign acquisition."

Sovereign citizens believe they should choose which laws they follow, according to the Southern Poverty Law Center. The movement is based on a conspiracy theory that the US government, as established by the founding fathers, was secretly replaced.

They do not believe in the authority of judges, juries, law enforcement, or elected officials, and most do not believe they should have to pay taxes. Sovereign citizens "clog up the courts with indecipherable filings" and sometimes engage in "paper terrorism" that involves tons of court filings with "pseudo-legal nonsense," according to the SPLC.

Police had tried multiple times to get the squatters to leave the home, including using a helicopter and armored vehicles, the Baltimore Sun reported. They were able to get a search warrant after pulling over Michael Lawrence Warren, one of the squatters, for a traffic stop and discovering his identity and criminal history, which included sex offenses.

Court records show Warren was arrested and charged with multiple counts of burglary and illegal possession of a firearm.

Another person implicated in the incident is Tessa Mona Modiri. Court records show she has also been arrested and charged with multiple counts of burglary. The Baltimore Sun said Modiri had filed a complaint with the county claiming the home belonged to her because she entered it through a broken door, arguing it was abandoned.

Tessa M. Modiri is listed as having an active dentist license in the state of Maryland's database.

There are three others facing burglary charges in the incident, but they have not yet been arrested.

The Baltimore Police Department did not immediately respond to a request from Insider for more information on the charges and arrests.

Sovereign citizens have attempted to take over other people's homes in the past. Last month, a self-proclaimed sovereign citizen was arrested after entering a woman's vacant home in New Jersey and changing the locks.

Another group affiliated with the sovereign citizen movement got into a heavily armed standoff with police on a Massachusetts freeway earlier this month. Police said the 11 men arrested referred to themselves as a militia that followed a "Moorish Sovereign Ideology," which is an offshoot of the sovereign citizen movement, experts told The Boston Globe.