After nearly a dozen people were stabbed at a Walmart in Traverse City, Michigan, Saturday afternoon, the quick actions of a couple of Marines and other bystanders helped stop the attacker from causing further harm.

The authorities on Sunday said that a motive for the attack, which left 11 people injured, remained unknown. Citizens, including one who was armed, helped to apprehend the suspect, officials said.

The stabbing spree at a Walmart near Traverse City left 11 people injured. The suspect appeared to randomly target the victims, according to police.