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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Argentina's president has announced plans to disband the country's intelligence services following the death of a state prosecutor.