TRAVERSE CITY, Mich. — Chaos unfolded at a Walmart in Michigan after a man burst into the store during a calm shopping afternoon and stabbed 11 people at random, authorities say. The attack on Saturday left six victims in critical condition and a suspect in custody.

The 42-year-old suspect entered the store shortly before 5 p.m. and used a folding knife to stab the victims, the Grand Traverse County Sheriff’s Office said in a statement on social media. Their ages weren’t immediately known.

A sheriff’s deputy arrived within minutes and took the man into custody.

Steven Carter was loading his truck in the Walmart parking lot when he saw a man cut a woman’s throat with a knife.

About five minutes later, the man was surrounded by shoppers in the parking lot, including one who was holding a gun. The group of five or six people kept yelling to the man ”drop the knife,” he said, and the man responded: ”I don’t care, I don’t care.” He kept backing away from the crowd, before someone tackled and subdued him.

”At first, it was disbelief. I thought maybe it was like a terror attack,” said Carter, who delivers customer orders from Walmart. ”And then it was fear, disbelief, shock. And that was, it was just amazing. And it all happened fast. Like he was totally subdued on the ground by the time police arrived.”

An update on the condition of the victims was expected early Sunday.

Emergency vehicles and uniformed first responders gathered in the parking lot of the shopping center that houses several other retail stores. Authorities also were seen interviewing employees, still wearing blue uniform vests and name tags, nearby as the response gave way to an investigation.