Michigan: 11 people stabbed in US supermarket - with six in critical condition

Officials say a suspect is in custody - and at this stage, it is believed the attack was a "random act" that involved a folding-style knife near the checkout area.

Sheriff Michael Shea told reporters: "Eleven is 11 too many, but thank God it wasn't more."

The suspect, who is from Michigan, is not known to police - and was captured within three minutes thanks to "citizen involvement".

The attack unfolded in Traverse City - and Tiffany DeFell, who was in the car park at the time, described scenes of chaos.

"It was really scary. Me and my sister were just freaking out," she said. "This is something you see out of the movies."

Beyond the six people in a critical condition, it is believed the remaining five were seriously hurt. All 11 are still being treated in hospital.

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Michigan Governor Gretchen Whitmer said: "Our thoughts are with the victims and the community reeling from this brutal act of violence."

A Walmart spokesperson added that the retailer is working closely with law enforcement.

"Violence like this is unacceptable. Our thoughts are with those who were injured and we're thankful for the swift action of first responders," a statement said.

At this stage, the ages of the victims is unclear - but it is not thought any of the victims were Walmart employees.

Traverse City is about 255 miles northwest of Detroit.

-SKY NEWS