Police got to the store on Harrison Avenue around 10:30 a.m. after someone called 911 to report an assault, CBS2's Jenna DeAngelis reported.
Police said they found a 43-year-old man inside the store with a deep cut and blood streaming down the back of his head.
As CBS2's Jessica Layton reports, police say the two strangers had an argument while standing in line and punches were thrown before the machete was swung.
"It was an altercation between two people and then they, one guy pulled out, it was like a sword and he cut it. People see him laying on the ground and one guy was bleeding from the head. It was terrible," witness Thomas Underwood said. "It was just a stampede of people who were running. One girl got trampled. She ended up going to the hospital. She got hurt, she hurt her leg."
The suspect left the store before officers arrived, police said.
The victim was taken to University Hospital in Newark. He was released after having the wound stapled closed.
Watch Jenna DeAngelis' report --
Investigators said they do not believe the suspect and the victim knew each other.
Shoppers were let back inside the store around 2:30 p.m.
"It was just total chaos. I was scared for my life," said a shopper.
She described the terrifying moments when she was trampled and hurt while running out of the Walmart.
"I was knocked to the floor instantaneously. At this moment, I don't know what's going on. I just saw dozens of people running towards the exit. Someone screamed he had a gun," she told DeAngelis.
"I just started seeing people screaming and running, and I'm like, 'What's going on?'" said Ray Martin, who saw the suspect swinging the weapon.
Martin believes the victim jumped in to stop the suspect, but police dispute his account. They say the men were throwing punches before the machete came out.
"It was crazy. Everybody just grabbed their kids and everybody ran," a Walmart employee said.
Chopper 2 video showed the line of fire and police vehicles outside the store.
Shoppers were left concerned.
"How did he even bring the machete in? Something so large, so visible. To even bring that in is beyond me," another shopper said. "It's a scary world out there and you just have to watch what we do and be aware of our surroundings."
Police said the suspect brought the machete into the store. It appeared to be hidden under his clothes.
"This is the first time we ever seen something crazy like this and I don't know if I'm coming back to this Walmart," another woman said.
Late Friday night, police said a suspect was arrested in Newark. Further details, including the suspect's identity, have not yet been released.
"We are shocked by Friday's incident and are hopeful the injured customer recovers quickly. We are grateful to law enforcement for their quick response and are helping them in any way we can," a Walmart spokesperson said.
CBS2's Jessica Layton contributed to this report. Editor's note: This story was first published Sept. 24.
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