The counting of ballots in the Scottish independence referendum is under way, with the first results expected in the next few hours.
Turnout is expected to reach record levels as voters came out in force to decide whether or not to remain part of the United Kingdom.
With no exit polls conducted during the historic ballot, a survey by polling company YouGov, which found 54% in favour of staying in the union, was the only pointer for people eager for an early clue to the result.
It based its prediction on the responses of 1,828 people after they voted today, as well as 800 people who had already cast their ballots by post.
All respondents had previously taken part in a voting intention survey earlier this week, allowing the company to assess any last-minute shifts in views.
The responses indicated a small shift on the day from Yes to No, and also that No supporters were slightly more likely to turn out to vote.
Some 10% of No voters said they had encountered unreasonable behaviour by Yes campaigners when they went to cast their ballots, while 5% of Yes voters said they witnessed unreasonable activity by the No camp.
The post-election poll was broadly in line with surveys in the final days before the referendum, which gave No a lead of between two and six points.
The referendum came more than three years after Alex Salmond’s SNP secured a landslide victory at Holyrood.
The chairman of Yes Scotland said he was not conceding defeat, despite a YouGov survey suggesting that Scots have rejected independence by a margin of 54%-46%.
Former Labour MP Dennis Canavan told Sky News: “I’m still optimistic … I’m not at this stage conceding the result.”
Mr Canavan said it was “probably correct” that today’s vote would settle the independence question for a lifetime.
He said that while the Yes camp had fought a “very positive campaign, a magnificent campaign”, the No message was characterised by “a bit of negative scaremongering going on, a bit of collaboration, perhaps even collusion, on the part of the British establishment”.
Liberal Democrat MP for Gordon and No supporter Malcolm Bruce said he believed that “reality has kicked in” with voters switching back to No after being briefly seduced by the Yes campaign’s message.
Mr Bruce said: “Certainly we felt that the campaign was swinging back to our side – if it ever really swung away to the extent that people suggested – both in terms of our canvassing and the responses we’ve been getting as people came out of the polling stations.
“I will be very well satisfied if the campaign to keep Scotland in the UK has succeeded. I believe it’s in the best interests of Scotland and the UK that that should happen.
“I think the agenda put forward by the Yes campaign is scary. To suggest we build a new state with no bank, no reserves, no currency and no visible means of financial support, in my view was totally irresponsible, but it was very plausible, it was very attractive to people who wanted to believe it. They were drawn into it by this positivity, but in the end reality I think has kicked in.”
Yes campaign wins Twitter battle
Meanwhile, the Yes campaign won the independence referendum battle on Twitter, the social network has revealed.
More than seven million tweets about the referendum have been sent since the first televised debate on 5 August, including 1.5m in the past 48 hours.
Overall, users posted more than 1.5m messages backing the Yes campaign, compared to 500,000 for No.
The most re-tweeted message on referendum day was Andy Murray’s endorsement of the Yes campaign, which was shared more than 18,000 times.
During the campaign, the most-used has tag overall was #IndyRef, Twitter said, with 3.75m mentions.
The #VoteYes message was used 1.1m times, followed by #Scotland at 439,000, #ScotDecides at 272,000, and #BetterTogether at 224,000.