On Sunday, Trump in a Twitter post responded to the mayor's statement after London terror attack, writing: "At least 7 dead and 48 wounded in terror attack and Mayor of London says there is ‘no reason to be alarmed!"
Trump continued feud with Khan on Monday and called the mayor's words "pathetic excuse."
Sanders contended that Trump was not "picking a fight" with the mayor, but rather reiterated his belief that the US has to be committed to national security.
Khan on Sunday expressed condolences to the relatives of those affected by the two terror incidents and condemned the act in the strongest possible terms.
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