Law enforcement agencies are looking for ways to mine social media to look for threats. Speakers at the Microsoft Public Safety Symposium spoke at a conference on Wednesday. New Zealand police set up a system that scrapes YouTube, Twitter and Flickr, plotting the message, photo and video uploads on a map. The system offered time stamps for when the tweets were made with a high granularity for where they were issued, he said. But over the six weeks of the World Cup, the system collected 20 million tweets.”]

