Donald Trump’s attempt to portray himself as a uniter, not a divider, was undermined by a shout from the crowd during his victory speech in the early hours of Wednesday morning.

Just moments after Trump declared it was “time for us to come together as one united people,” one of his supporters shouted what sounded to many listeners like “Kill Obama!”

Others suggested the plea was to “jail Obama,” but the moment stunned many viewers, raising fears that, just as the victory of nationalists in Britain’s vote to leave the European Union was followed by an ugly wave of hostility towards foreigners, Trump’s election might seem to ratify the open racism and calls to political violence that had punctuated his campaign.

While Trump’s young son, Barron, appeared to express shock at the outburst, the president-elect, if he heard it, chose not to react.