Police have been asked to investigate whether members of the Better Together campaign breached electoral law by revealing Scottish referendum postal votes before the polls closed.

A number of complaints were made to the Electoral Commission after Ruth Davidson, the leader of the Scottish Conservatives, said 45 minutes after the polls closed she was "incredibly encouraged" after 'No' campaign agents had been "taking tallies" of postal votes in sample openings weeks prior to the count.

Whilst opening of ballot boxes by campaign agents in the days and weeks before the voting officially closes is a routine procedure, it is a criminal offence to reveal the results of these openings. Any agents found guilty of doing so can face up to 12 months in prison and a fine of up to £5,000.

Agents from both the Yes and No campaign attended sample postal vote openings to check signatures and dates of birth matched the official records.

The Electoral Commission says ballots must be kept face down during proceedings to make sure no one else can see the result. The Scottish Independence Referendum Act 2013 adds these agents must not reveal the outcome of any vote or "communicate any information with respect thereto obtained at those proceedings".

The Electoral Commission confirmed it had received a complaint following Davidson's comments to the BBC and passed it the on to the police

Police Scotland said the complaints were being assessed. A spokesperson said even if a crime has been committed it will have no bearing on the result.

The complaints came after Davidson told Scotland Decides: "We have had people at every sample opening around the country over the last few weeks... and we have been incredibly encouraged by the results from that.

"Going into today, going by the postal votes that were cast, our side would have had a lead and I think that we have a confidence, I hope a quiet confidence, that the quiet majority of Scots have spoken today."

"Different local authorities have had openings around the country. It is illegal to discuss that while any ballot is ongoing, so until ten o'clock tonight no one could talk about it.

"But there are people in the room that have been sampling those ballot boxes as they have been opened and they have been taking tallies and the reports have been very positive for us."

A Scottish Conservative spokesman said: "We acknowledge the concerns of the Electoral Commission put to Police Scotland. We will cooperate with regard to any complaints made if asked to do so."