The disaster for the SNP has escalated even additional, as Scotland's chief constable has confirmed that the police investigation into the celebration's funds has been expanded.

The scope of the investigation will now embrace allegations of "misuse of funds" and "potential embezzlement", Sir Iain Livingstone confirmed.

Operation Branchform was initially a fraud investigation.

Police Scotland is investigating whether or not £660,000 raised by the SNP for a second independence referendum was spent on different issues.

Speaking to BBC Radio 4's Today programme, Sir Iain stated: "It’s moved beyond what some of the initial reports were."

When requested why the investigation has taken greater than two years, Sir Iain defined: "Investigations into the finances of an organisation, the finances of an individual, are often complex.

"Investigations round fraud or investigations round potential embezzlement or investigations across the misuse of funds take time.

"You need to go and obtain information from banks and other financial institutions.

"We can’t simply try this mechanically."

He added: "We must go and search judicial warrants for that. There must be a course of round that. So the time that’s been taken, in my judgment, is completely obligatory. There’s been a prudent, thorough and proportionate investigation carried out."

When requested whether or not he felt it was proportionate to place a police tent on former SNP chief Nicola Sturgeon's entrance garden, Sir Iain advised the BBC it was "proportionate and obligatory".

He said: "It completely was given the circumstances of that search."

"The tent was there, in addition to all the opposite measures, to guard the pursuits of justice and to guard the people concerned.

"So it was a proportionate and necessary step."

Ms Sturgeon and her husband Peter Murrell, the previous SNP chief government, have each been arrested and launched with out cost int he investigation.

The celebration's former Treasurer Colin Beattie has additionally been arrested and launched with out cost.