Donald Trump accused of falsely vilifying migrants for surge in US fentanyl deaths

Former head of US border security says claim ‘terribly misleading’ and statistics show nine of 10 convicted traffickers are US citizens

A former head of US border security has accused Donald Trump of “exploiting” the pain of the opioid epidemic to wrongly vilify migrants as responsible for the surge in American deaths from fentanyl during recent years.

But the Trump campaign is expected to double down on the deception now that the vice-president, Kamala Harris, whom Republicans describe as Joe Biden’s “border czar” and accuse of inaction over a surge of illegal immigration, is likely to be the Democratic presidential candidate in November.