Sixteen digital billboards have been placed along Arizona's freeways advertising the $50,000 reward for information leading to the arrest of the shooter, or shooters, who've fired at vehicles along those freeways over the last few weeks.
Department of Public Safety spokesman Bart Graves said finding the suspected gunman, or gunmen, is the agency's "number 1 priority" and that the investigation is active and ongoing.
He said nearly 1,000 tips have been submitted via the DPS and Silent Witness tip line. Of those, 550 were considered to be legitimate and troopers are actively investigating those leads, said Graves.
"We continue to ask for that one tip that's going to lead us to the arrest of this person responsible," he said at a Wednesday afternoon briefing with reporters.
Submit a tip to DPS at 602-644-5805 or Silent Witness at 480-WITNESS
Officials also passed out 10,000 paper fliers to Valley neighborhoods hoping to inform those about the case who may have missed media coverage. The fliers were donated by a local company.
"[Some people] may have been out of the loop on this investigation," said Bart Graves, a DPS spokesman, about the need for paper handouts in a world of smartphones and Facebook sharing.
Prisma Graphic printed nearly 200,000 fliers as a public service, he said.
MAP: View billboard locations and shooting incidents under investigation below:
Blue icon - Locations of DPS digital billboards
Crosshair - Confirmed locations under investigation by DPS
Yellow crosshair - Incident involved a bullet
Orange crosshair - Incident involved a projectile
Triangle - Possible incident not confirmed to be related to the investigation
There has not been a confirmed shooting incident since September 10. There have been several reports of broken windshields since then, but most have been caused by road debris and ruled out.
On Wednesday, Maricopa County Attorney General Bill Montgomery said generally the incidents can be considered domestic terrorism, but said Arizona's state laws focus on protecting public utilities and do not apply to the shootings case.
No arrests have been made in the case. A 19-year-old was arrested last week related to the investigation, but was booked into jail on an unrelated marijuana charge. DPS officials called the teen a "person of interest" and have not named him as a suspect.
Several schools around the Valley, including Arizona State University, have re-directed buses to avoid Interstate 10.
Officials continue to encourage the public to take notice of their surroundings and to contact authorities if they see anything suspicious.
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