Dow futures plunged more than 800 points and bonds rallied as markets feared Donald Trump could pull off an upset and take the White House.
S&P 500 futures fell more than 5 percent just before midnight ET. Trade volume in eMini S&P futures was about 17 times their average daily volume, according to a note from Citi.
Investors moved into the safety of bonds Tuesday evening and stock futures cratered as traders questioned whether Democrat Hillary Clinton could still win the race, as expected. The Mexican peso fell 10 percent against the U.S. dollar.
"Right now, the markets are heading for the hills, but we'll see," said Robert Tipp, chief investment strategist, global bonds and foreign exchange at Prudential Fixed Income. "That's a function of fear as much as fact.." Tipp said it's not clear whether Trump would be as disruptive as the markets worry he could be, since it's unclear what parts of his platform would be pursued and what type of individuals he would choose for his cabinet.
U.S. futures have been volatile as election results started rolling out at around 7 p.m. ET. Dow futures were up as much as 100 points at one point, and later down more than 700 points.
Keith Parker, global equity strategist at Barclays, had studied what might happen if Trump were to win and he projects the S&P 500 could move initially to around 2000, if the Republican businessman prevails. The S&P 500 ended Tuesday's session higher, up 8 at 2,139, as markets speculated that Clinton was in the lead.
"Markets would be volatile. Equities would take their cue from confidence indicators - what Trump says, what the GOP leadership does," he said.
Trump was the projected winner in some important battleground states, including Florida and North Carolina, but others remained too close to call. While the winner has yet to be determined, Trump's showing was much stronger than expected.

