The principal of Columbine High School has offered his condolences to the families of the victims killed during a school shooting in Newtown, Connecticut.
"It's a reminder of how vulnerable we are as a society," he said.
"As a society we have to come together, we have to stop these senseless deaths." reports the Denver Post.
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An extra hour a day of TV, internet or computer gaming could reduce GCSE success by two grades, research claims.
David Cameron is expected to announce a new plan that will see Britain take in thousands more Syrian refugees.
Reports Ed Miliband is to rule out a return to frontline politics have been described as "speculation" by sources close to the politician.