A Walmart employee was helping a customer check out when she heard a warning that someone in the store had a knife.

One of the men who authorities say helped take down a suspect who stabbed eleven people at a Walmart told NBC News about how he sprung into action. Marine veteran Matthew Kolakowski says he took off running after the suspect and rammed him with a grocery cart to prevent him from hurting more people.

A weekend stabbing spree at a Michigan Walmart initially left 11 injured, including six critically. As of the latest update, 10 people remain hospitalized and are being treated for their injuries, according to officials. The attack began at the Traverse City store around 4:43 p.m. local time on July 26.