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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The twin brother of the police officer shot and blinded by gunman Raoul Moat says his family are still waiting for justice five years later.
The success of the No camp is mainly due to Tsipras convincing people a No vote will strengthen their hands in negotiations.
As we move into the weekend, expect things to get rather more unsettled weather-wise - thought it will stay hot and humid for some.