The White House has said President Obama has been briefed on the shooting incident at LAX Airport.
White House officials are in touch with law enforcement officials on the ground, White House spokesman Jay Carney told reporters.
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The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.