Dow futures have plunged 600 points and bonds have rallied as traders questioned whether Democrat Hillary Clinton can win the presidential election as expected.
The Asian stock market is also in freefall.
Traders have been watching for the outcome of the battle for Florida as they were looking to get an early projection there.
The Mexican peso was down as much as 5 % against the dollar.
Donald Trump has controversially said he would build a wall along Mexico’s northern border and break trade deals with Mexico.
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