Britons waited nervously as counting went on through the night for a historic vote on whether to quit the European Union, as final polls showed the Remain camp edging ahead.
Storms that lashed south-eastern England yesterday, including London, caused flooding in many areas, affecting polling stations and disrupting train networks during the morning rush hour.
But the wet weather hardly deterred voters. Some had to be carried into polling stations while others were lent boots to wade through ankle-deep water.
Carpenter Liam Collins, 45, umbrella in hand, was already at his polling station in a church in Rotherhithe in south-east London when the polls opened at 7am.
"It's one of the most important decisions this country will make. It affects everyone," he said, after casting his ballot for Remain.
A record 46.5 million people registered to vote in only the third referendum in the country's history.
The final opinion polls were divided on which side was leading.
Pollster ComRes found Remain had strengthened at 54 per cent to Leave's 46 per cent; YouGov had Remain at 51 per cent and Leave at 49 per cent, while TNS and Opinium both showed Remain was trailing Leave at 49 per cent.
Two surveys released on polling day showed Remain had an edge.
Financial markets rallied yesterday, with shares at their highest level since late April, while the pound was its strongest since December, hitting US$1.4931 at mid-morning, reflecting traders' optimism that Remain will prevail when the result is announced around breakfast time today in Singapore.
Even as voters made their way to polling stations, thousands of volunteers fanned out to train stations and high streets across the country, distributing leaflets and stickers.
"We're all out there today, reminding people to vote," said a volunteer from the official Remain campaign - Britain Stronger In Europe - as he cajoled commuters outside the Shoreditch station to wear a "Vote Remain Today" sticker.
Immigration has been a major focus of the Leave campaign, which wants tougher curbs. The Office of National Statistics released figures yesterday showing that Britain's population rose by more than half a million in a year to 65 million.
"The issue that matters is immigration," said retiree Barry Martin, 69, outside a polling station in Biggin Hill, a commuter town south of London. "They're just coming in willy-nilly. You see it in the papers every day, they're getting on lorries, coming over from Calais (in France)," Agence France-Presse quoted him as saying.
The nation's divisions were reflected in newspapers' front pages. "Independence Day" was the front-page headline of the Sun tabloid, Britain's biggest-selling newspaper, while the Daily Mirror warned, "Don't take a leap into the dark".
Ms Lauren Rickard, 24, a digital marketing assistant who voted Remain, said she fears that she will wake up this morning to news that Leave won. She said: "In no way do I think that the country is being run perfectly, but I do think that the EU brings in a lot of money for Britain, and brings other benefits that can't be ignored."
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