In an ABC News exclusive, Derrick Perry recounts his confrontation and pulling his gun on the man accused of stabbing 11 people at a Michigan Walmart.

Grand Traverse County Sheriff Michael Shea said the “remarkable” efforts of the bystanders likely prevented others from being harmed.

The suspect in the mass stabbing attack at a Traverse City, MI, Walmart store is seen in a viral video that shows a bystander stopping him at gunpoint as other heroic citizens also intervened. The founder of a local scanner page wrote on Facebook that two Marine veterans were involved in ...