Stabbing suspect Bradford James Gille was subdued within minutes with the help of bystanders, authorities said.

Michigan authorities said Sunday they are seeking to file terrorism charges and 11 charges of assault with intent to murder against a 42-year-old man accused of carrying out a knife attack at a Walmart store.

"I'm still sitting and grappling with the weight of realizing that it was kind of a life-or-death moment," said Julia Martell, who witnessed the stabbing, which wounded 11 people.