A North Dakota farmer convicted of terrorizing law officers two years ago is the first American to be sentenced to prison with the help of a Predator drone, Forbes reported.

Rodney Brossart, who was accused at the time of stealing six cows from a neighbor, was arrested after a summer-long standoff in 2011. Authorities say Brossart family members refused to allow deputies on their farmstead and didn't show up for court hearings.

The case drew widespread attention because police used a military-style unmanned drone to conduct surveillance on the Brossart farm. Brossart was found not guilty of stealing the cows and got six months in prison over the police standoff, Forbes reported.

Brossart's attorney asked a judge to drop the charges because he said the drone use was done without a warrant. The judge, however, rejected the motion, the report said.

Prosecutors earlier dropped charges against Brossart's wife and daughter. His three sons also are charged with terrorizing. Their trials haven't been scheduled.

The Forbes report points out that CBP Predator drones flew 700 missions for law enforcement in the U.S. between 2010 and 2012.