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 work and pensions secretary is said to be thinking of throwing his hat in the ring for leadership of the Tory party.
Prior to the EU referendum Boris Johnson spoke to ITV News National Editor, Allegra Stratton, on what a post-Brexit UK would look like.
The woman, called Karen, was in tears as she spoke about the xenophobic attacks she has suffered since the EU referendum.