Police arrested David Allen Brutsche, 42, and his female roommate, Devon Campbell Newman, 67, Tuesday, after a four-month investigation, the Las Vegas Sun reported.
"As the investigation progressed, we became aware that these two individuals were extremists in their beliefs and were actively plotting to kidnap and kill at least one southern Nevada police officer," Lt. Jim Seebock of the department's counter-terrorism department told CNN.
He said no particular officer was singled out and that the victim was to be a "target of opportunity."
"The suspects further believed once the first kidnapping and execution was accomplished, they would be compelled to keep repeating their actions -- kidnapping and killing multiple officers," Seebock said.
Police said that during a sting operation both suspects expressed views of the Sovereign Citizens movement, which does not recognize the authority of government.
Undercover officers infiltrated the group and had met with the suspects about 30 times since April, the Sun reported.
Brutsche and Newman were charged with conspiracy to commit murder, conspiracy to commit kidnapping and first-degree kidnapping with a use of a weapon, police said.
Brutsche, who is a six-time convicted felon and a registered sex offender, said he committed no crimes.
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