Three people were killed and atleast three more critically injured after a lone gunman opened fire at a shopping mall in Copenhagen, Denmark on Sunday evening. A 22-year-old Danish man was arrested after the shooting, Copenhagen police said. Soon after the shooting began, footage was posted on social media of people running through and out of the mall. A grainy video of a man holding a rifle wearing shorts and t-shirt was also posted. Denmark’s government has not declared the shooting a terrorist attack.