A group of US mayors joined forces with survivors of the Tucson gun rampage on Sunday to step up their campaign for tighter gun controls in the wake of the recent mass killing in Aurora, Colorado. Mayors Against Illegal Guns, the bipartisan coalition of more than 700 mayors including New York's Michael Bloomberg, released a television advertisement during Olympics coverage and the US's top politics shows calling for president Barack Obama and his rival governor Mitt... (GunPolicy.org)