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 practice of sending mental health patients far away from friends and family for care has become endemic in the NHS, it has been warned.
Despite the use of combustible cladding in tower blocks, ministers were advised that regulations were tough enough, ITV News has learnt.
A milder night across the north than last night, with rain sneaking into southern Scotland from Northern Ireland.