Arizona Freeway Shootings: Man Being Questioned Booked on Unrelated Charges Police said Thursday they were investigating at least 11 separate incidents.

 -- Authorities in Arizona said today that they were questioning one person in connection with a spate of shootings that targeted the heavily-traveled Interstate 10 freeway near Phoenix, leaving commuters terrified for weeks.

According to ABC News affiliate ABC15.com, officers with the state's Department of Public Safety surrounded a white Chevy Tahoe at a Chevron gas station about 2.4 miles from I-10. ABC15.com said a woman was driving the vehicle and a male was riding in the passenger seat. Both individuals were taken into custody.

The Department of Public Safety said the duo were a mother and son. Authorities said while the mother had been released, the son was still being questioned. It was not clear how old he is.

Police said Friday night the son was booked on unrelated charges. It was not clear what those charges were.

Workers at a dental office near the Chevron station told ABC News that they noticed police waiting outside around 7:40 a.m.

Investigators said Thursday that they were investigating at least 11 separate shooting incidents along I-10, after they confirmed a bullet hole found in the side of a truck today.

Col. Frank Milstead, director of the state's Department of Public Safety, told ABC News on Wednesday that it was unclear whether all of the incidents are related and was also unclear whether all incidents involved bullets.

He classified the incidents as "domestic terrorism," calling the person or people responsible cowards who are putting innocent lives at risk.

"What I say 'domestic terrorism,' I don't know what else you would call it. When you're, you know, inflicting terror on a community, what else is it?" he said. "These are bad people trying to do harm to good people."

The department said that the incidents dated back to Aug. 29, 2015 and that every shooting had happened along a short eight-mile stretch of road.

"We have a hard crime to solve because it's such a large area and there so many different vantage points for someone who wants to do something wrong," Milstead said.

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