PHOENIX (AP) - A suspect was arrested Friday in a string of shootings that has kept drivers on edge for weeks as vehicles were struck with seemingly random gunfire as they drove down Phoenix freeways.

Leslie Allen Merritt Jr., 21, was arrested at a Wal-Mart in Glendale, a suburb west of Phoenix at 7 p.m., said Daniel Scarpinato, a spokesman for Gov. Doug Ducey.

Department of Public Safety Director Frank Milstead announced the arrest at a news conference two hours later, saying a suspect was arrested in four of the 11 shootings. Merritt has not been formally charged yet.

Milstead said the suspect was arrested in the first four shootings, which took place on Aug. 29 and 30. The agency says the man faces a range of charges that include criminal endangerment, assault and unlawful discharge of a firearm. Milstead has previously called the incidents "domestic terrorism crimes."

The four shootings that police say he committed hit a tour bus, an SUV and two cars, all of them on Interstate 10. No one was injured.

"Are there others out there? Are there copycats? That is possible," Milstead said, adding that the investigation continues.

Phoenix City Councilman Sal DiCiccio, who received updates about the arrest from the police department, said the arrest was made after the suspect tried to pawn the gun used in the shootings

"We got him!" Ducey tweeted. "Great work by Arizona DPS investigators and SWAT team."

Since Aug. 29, there have been 11 confirmed shootings of vehicles in the Phoenix area involving bullets or other projectiles. Most occurred along Interstate 10, a major route through the city. The Wal-Mart where the suspect was arrested is 6 miles north of where some of the shootings on I-10 occurred.

There have been no serious injuries, though a 13-year-old girl's ear was cut by glass after a bullet shattered a window of a vehicle she was riding in.

There has not been a confirmed shooting in the case since Sept. 10.

The shootings have prompted several school districts to keep their buses off freeways, and some motorists have altered their commutes to avoid driving I-10.

Authorities offered a $50,000 reward for information leading to an arrest and conviction in the case. They distributed thousands of fliers in neighborhoods along the freeway this week to raise awareness about the shootings and the reward, but they have been tight-lipped about any details in the case.

The Arizona Department of Public Safety said state troopers have stepped up patrols, while other agencies assisting in the investigation have included Phoenix, Tempe and Mesa police as well as the FBI and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

"I think it's fair to say since a week ago, we've made headway in this case," Department of Public Safety spokesman Bart Graves said earlier Friday.