WILLCOX, Ariz. (AP) — Authorities are working to determine what motivated a man to allegedly fire a rifle indiscriminately at a southeastern Arizona high school, injuring 17-year-old boy who was watching a baseball game.

The student suffered minor cuts from flying glass when the car he was in was shot at Thursday, authorities said.

Arthur J. Tineo, 40, was arrested shortly after the shooting at Willcox High School, and the weapon he is accused of using was recovered about a block south of the scene, according to the Willcox Department of Public Safety.

DPS Chief Jake Weaver said authorities believe Tineo fired three rounds, but they don’t yet know the motive for the shooting in the small high-desert town about 200 miles southeast of Phoenix. It happened shortly after 3 p.m., after classes were done for the day.

Another juvenile in the same car escaped injury, and authorities said a school employee was fired upon as he was trying to clear the area during the shooting. No other injuries were reported among the spectators watching a varsity baseball game between Willcox High and Valley Union High.

Weaver said Tineo, of Willcox, was booked into Cochise County Jail on suspicion of three counts of attempted murder, plus charges of assault, endangerment, aggravated assault with a deadly weapon, prohibited possession of a firearm, disorderly conduct with a weapon, and discharging a weapon within city limits.

“We don’t know if he had a specific target because our officers haven’t had a chance to talk to him yet, but it appears he was firing indiscriminately,” Weaver said. “We don’t know what his motive was at this time.”

It was unclear whether Tineo had a lawyer yet.

Weaver said Tineo “does have a record” but he couldn’t immediately provide details about his prior offenses.

Willcox DPS responded after receiving a 911 call about a man in a field across from the school’s baseball field, shooting a rifle toward the campus grounds. The area was locked down for several hours until authorities “felt comfortable” that only one suspect was involved and that person was in custody, Weaver said.

About 500 students from the Willcox area attend the high school. The city has a population of about 3,800 and still has the feel of the Old West with its antique shops and museums.