A man who later killed himself allegedly shot at three people Wednesday morning near an Upper Macungie Township Wawa. A trucker was killed while gassing up his rig and another man was injured, Lehigh County District Attorney Jim Martin said at a news conference in the parking lot where the early-morning violence unfolded.

The Lehigh County Coroner’s Office identified the shooter as Za Uk Lian, 45, of South Whitehall Township. The truck driver he killed in what law enforcement officials are calling an “indiscriminate” shooting rampage was identified as Ramon Ramirez, 31, of Allentown.

The incident began before sunrise when the shooter, who was driving a white Toyota Corolla, had an “encounter” with a female driver between Route 309 and Cedar Crest Boulevard and fired a single shot at her car. Martin said the woman wasn’t injured and didn’t realize she’d been shot at until she pulled into the Wawa.

“She came here to get a sandwich, and when she came out of the Wawa, she realized that there was a bullet hole in her car,” Martin said.

The shooter, he added, pulled in behind her.

Martin said the shooter drove to the other side of the store, parked beside a Jeep, and shot at the driver, who received treatment and is expected to survive. Then the shooter turned his gun on Ramirez, the truck driver, who was getting gas when he was fatally shot.

Next, the gunman fled on foot to Brookside Children’s Early Education Center, a daycare about a quarter mile away that was closed at the time, and fatally shot himself in the hand and chest, Martin said.

He commended the quick action of a Wawa employee, who heard gunshots while he was taking out the trash and ushered two prospective customers inside the store, where customers and employees sheltered in place together.

“All credit to him,” Martin said.

One of those customers was Matthew Caldwell, 32, of Bethlehem, who told the Morning Call that his brush with deadly gun violence early on his way to buy a Red Bull energy drink didn’t seem real.

“Your instincts kick in and you don’t want to die,” said Caldwell, who was sitting in his car, sending a text message, when he heard gunfire and shattering glass. He was parked beside the Jeep the shooter struck.

Caldwell said he immediately jumped out of his car and dropped to the ground. He watched as the driver of the Jeep fell from the vehicle, screaming for help and bleeding heavily. And a few moments later, he bolted to the back of the store and found the Wawa employee who helped him inside.

Through the store’s glass windows, he watched as people performed CPR on Ramirez.

“I was terrified,” he said, his voice shaking. “I didn’t know where he was. I didn’t know if he was walking or drove away.”

At least two dozen police vehicles from the township, surrounding municipalities, and state police responded to the shooting, the Morning Call reported, which comes on the heels of several high-profile mass shootings in cities across the country.

Multiple roads were closed due to the police response.

Businesses in the area, which is home to major warehouses like Ocean Spray and Nestle, entered lockdowns due to the shooting, and the Parkland School District closed nearby Fogelsville Elementary School for the day.

Arthur Sanchez, a security guard who visits the Wawa most mornings, told the Morning Call that he had missed his exit and arrived a little later than usual. He saw police cars and ambulances arriving just as he pulled into the parking lot.

Sanchez said he parked next to an orange Jeep Wrangler that had been pierced by bullet holes and was surrounded by shattered glass from a broken passenger-side window. When he asked a bystander what happened, the person told him someone had “started shooting, and everybody started running.”

Stephanie Sigafoos, Jennifer Sheehan, and Daniel Patrick Sheehan from the Allentown Morning Call contributed to this article.