It's been one month since string of shootings along Arizona freeways first began and kept motorists on edge as they made their daily commutes.
In total, Arizona authorities are investigating 11 confirmed shootings that happened along Interstate 10, Interstate 17 and Loop 202 between August 22 and September 10, the last date of a confirmed incident.
One man, Leslie Merritt Jr., has been arrested and indicted on 15 felony counts related to the investigation. Merritt is believed to be the "prime suspect" in the first four shootings, which occurred between August 22 and August 30, according to authorities.
He is scheduled to be arraigned in court on Thursday morning.
There has not been a suspect arrested in the remaining seven incidents.
Nineteen-year-old Oscar de la Torre Munoz was detained by Arizona Department of Public Safety troopers on Sept. 11 and held behind bars for a week on an unrelated marijuana charge before being released by court order after officials failed to submit proper charging documents.
Authorities say Munoz was never officially called a suspect, only a “person of interest” and that he has not been ruled out of the investigation.
The “I-10 Shooter Tip Line” alerts have also been taken down from the electronic monitors that hang above all of Arizona’s freeways, but DPS still has electronic billboards posted along I-10 and I-17.
DPS spokesman Bart Graves said calls into the tip line via DPS or Silent Witness have “decreased substantially” since Merritt’s arrest, but they encourage the public to call in with any additional information they may have.
Of the 11 confirmed incidents, eight involved bullets and the remaining involved projectiles, which could be a bb, road debris, or something else.
DPS said it used ballistic evidence from the first shootings to determine which guns may have been used in the shootings. They then put out requests for any guns that had been pawned recently.
According to DPS, Merritt pawned his gun after the shootings, a notion the suspect denied at his first court appearance.
"I'm the wrong guy...My gun has been in the pawn shop for the last two months," the suspect told the judge.
While the ballistics may be a match, according to authorities, it may be an uphill battle to guarantee a conviction.
"You still have to put him at the scene and prove he was the one that actually used the weapon," said Bradley Garrett, a former FBI agent and criminal investigations expert.
Merritt remains behind bars on a $1 million bond.