"So these congresswomen, their comments are helping to fuel the rise of a dangerous, militant hard left," Donald Trump said to roars from the crowd in North Carolina, a state seen as key to his re-election.
Mexico sends around 80% of its exports to the United States, and Trump last month vowed to impose tariffs on all Mexican goods if Lopez Obrador does not reduce the flow of U.S.-bound illegal immigration from Central America.
Trump has pledged to use his presidential powers to trigger the tariffs as soon as next week unless Mexico makes progress on slowing the flow of migrants from Central America arriving at the southern US border.
Federal prosecutors announced Friday that Patrick Carlineo Jr. was arrested after placing a threatening call to Omar's office in Washington D.C. last month. Authorities did not say when Carlineo was arrested.
Under the United States GSP programme, nearly 2,000 products including auto components and textile materials can enter the US duty-free if the beneficiary developing countries meet the eligibility criteria established by the Congress.
A 42-year-old Muslim woman has won the Democratic nomination to run unopposed for a House seat in Michigan, bringing her closer to becoming the first female from the minority community to be elected to the US Congress, according to a media report.