Tokyo stocks plunged Wednesday as early results suggested that market-favoured Hillary Clinton is struggling in her bitter battle against Donald Trump for the US presidency.
The benchmark Nikkei 225 index dropped 2.2 percent, or 382.48 points, to 16,788.90 by the lunch break, after swinging between gains and losses for most of the morning as election results trickled in.
The broader Topix index of all first-section shares dived 2.26 percent, or 30.85 points, to 1,332.64.
The latest results showed the rivals were locked in a dead heat in key battlegrounds, after markets had largely been betting on Clinton, who is seen as a safer pair of hands by the markets.
"We're being thrown this way and that over the voting results," said Tomoichiro Kubota, a senior analyst at Matsui Securities in Tokyo.
A deeply divided electorate of about 200 million Americans were asked to make a momentous choice between electing the nation's first woman president, or handing the reins of power to a billionaire populist who has upended US politics with his improbable outsider campaign.
With voting over in most eastern states and Americans still lining up to cast their ballots on the West Coast, television networks called 16 states so far for Trump -- a band of red on the electoral map stretching from South Carolina to Texas.
With Trump making a stronger-than-expected showing, investors pushed into the yen, which is bad for Japanese stocks.
The currency is seen as a safe investment in times of uncertainty, but a stronger yen is bad for Japanese exporters' profitability and tends to spark selling of their shares.
In Tokyo, the dollar slumped to 102.52 yen from above 105 yen seen earlier in the day.
The Mexican peso, which has become a proxy for the property mogul's chances of taking the White House, hit as low as 19.8619 to the US dollar, down almost 10 percent from its high earlier in the session.
