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 announcement is part of a £500 million cost-cutting drive which will take place over three years.
A chilly north for the glens of northern Scotland and the Highlands but otherwise a frost free and generally mild night.
The former US president has suggested some of those who voted for Brexit may only now be realising the impact of their decision