SIOUX FALLS - A man tried to run an off-duty Sioux Falls Police Department officer and his family off the road on Sunday afternoon.

Faron Regan Rehm, 27, was driving near 69th Street and Louise Avenue when he passed the vehicle of an off-duty officer, his wife and three kids, police spokesman Sam Clemens said. Rehm tried to switch lanes and narrowly missed the officer’s vehicle.

The officer initially thought Rehm had made a mistake. The second time, however, Rehm nearly forced the officer’s vehicle off the road, Clemens said.

The off-duty officer than followed Rehm’s vehicle to an apartment building parking lot in the 3600 block of W. 85th Street and identified himself as he approached the erratic driver. Rehm attacked at that point, Clemens said, taking swings and eventually grabbing a knife, which the off-duty officer was able to knock out of his hand.

Rehm went into his girlfriend’s apartment, and came back out and began to fight with the off-duty officer again before an on-duty police officer arrived at the scene.

The off-duty officer, his wife and his 3 children were unharmed. Rehm was also unhurt.

Faron Regan Rehm, 27, was charged with one count of aggravated assault, one count of aggravated assault against a law enforcement officer and one count of reckless driving.