Carnage came to world markets on Friday as early voting returns suggested Britain was on the brink of leaving the European Union, threatening the existence of the entire bloc and its single currency.
Risk assets were scorched as investors fled to the safety of top-rated government debt, with FTSE futures off 6 percent and EMINI S&P 500 futures down 2.5 percent.
At one stage the British pound had collapsed no less than 10 U.S. cents, its biggest fall in living memory, while the euro slid 2 percent as investors feared for its future.
Sterling was last down a huge 5.8 percent at $1.4063, having carved out a range of $1.3969 to $1.5022. The fall was even larger than during the global financial crisis and the currency was moving one or two cents in the blink of an eye.
"Sterling is getting smackadoodled," said Tim Kelleher, Head of FX Institutional Sales New Zealand for ASB Bank in Auckland. "While we thought it was all going to be "Remain", it's quite clearly not going to be as clear cut as that."
Early official results showed the margins were nail-bitingly tight but pointing to a "Leave". Betting firm BetFair estimated the probability of leaving as high as 74 percent.
Traders were particularly spooked by returns from Sunderland showing a large majority for the "Leave" camp and just a narrow win for "Remain" in Newcastle.
With 171 of 382 counting areas declared, the Leave camp was put at 51.3 percent against 48.7 percent for "Remain", according to Reuters calculations.
The tremors shook all asset classes and regions.
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