Trump Denies Reports That He Will Reinstate Family Separations, Blames Obama for Policy

President Trump’s purge of the nation’s top homeland security officials is a sign that he is preparing to unleash an even fiercer assault on immigration, including a possible return of his controversial decision last summer to separate migrant children from their parents, current and former administration officials said Monday.

Mr. Trump shook up the ranks of his top immigration officials after spending months demanding that they take tougher action to stop the surge in migrant families at the border and seething about what he considers their overly legalistic refusals to...