Authorities said a vehicle was shot up but no one was injured.

By: KDKA-TV’s Jennifer Borrasso and Royce Jones

PITTSBURGH (KDKA) — Police are investigating after shots were fired outside the Walmart in the Waterworks Shopping Plaza, authorities said.

(Photo Credit: KDKA)

Pittsburgh Public Safety Director Wendell Hissrich said a vehicle was shot up in the parking lot on Tuesday, but no one was injured. There was a person in the backseat who was waiting for a relative inside the store, Hissrich said.

“How he escaped is what I would consider a miracle,” Hissrich said.

Officials said the person in the vehicle had no connection to the suspects in this incident.

The Public Safety director said four suspects were involved. He said the four were inside the store, came outside to the parking lot, and that is when the shooting happened.

He said three fled the scene and one was thought to be inside the store. A tactical team cleared the Walmart, and no suspects were found, authorities said.

Officials believe some of the suspects got away in a vehicle. Police have not provided a description of the suspects.

(Photo Credit: KDKA)

“We think the shooting was the result of a domestic situation,” Hissrich said. “However, we have no suspects.”

A witness told KDKA’s Jennifer Borrasso over the phone that she heard gunshots at around 5:30 p.m. after she saw two men arguing outside the store.

The witness said that is when the store started evacuating customers.

“It was like clap, clap, clap, it was like cement bags hitting a marble floor,” another witness, Chuck Foster, said.

“It was commotion before that, and then clearly loud pops,” he added.

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More than 100 shoppers and dozens of employees were ushered to a restaurant across the street while law enforcement cleared the scene.

“We heard a commotion and it was the staff yelling for everybody to immediately get out of the store,” customer Kevin Dumas said.

A Walmart employee who did not want to be identified told KDKA he was working inside and was alerted by his manager that, “There’s an active shooter.”

He said the shooting incident was something he and his coworkers were more than prepared for. The employee said they had active shooting training in the past.

“We hear about it a lot. We see and watch the tapes. We’re prepared to do it, and everybody was organized,” the employee said.

Once officers cleared the scene, the store was closed for the evening, and workers were sent home.

Public Safety said the investigation has been turned over to the Crime Scene Unit.