In Germany, one person was killed and six injured in a knife attack at a supermarket in Hamburg. Police said, the suspect, born in the United Arab Emirates, acted alone and was, later, overpowered by passersby. The attack is being investigated.<br/> <br/>Germany has been on high alert about the threat of a terror attack since Amri's rampage in Berlin, for which the Islamic State group claimed responsibility.<br/> <br/>Terrorists have also carried out a string of random assaults in European countries using knives.