Denver officials said they are not aware of any threats made to President Barack Obama's campaign, but are exploring all possibilities as they investigate the shooting at his re-election headquarters.
Right now, no one is in custody and investigators are looking at surveillance video to see if a vehicle can be identified.
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A "torpedo" filled with 165lbs of cocaine with a street value of £4.4 million has been found on an Irish beach close to a tourist hotspot.
A 76-year-old millionaire businesswoman has been taken from her car and kidnapped by an "organised gang".
A quiet and calm afternoon with many places staying dry