The force said in a statement on Thursday it had submitted a "standard prosecution report" to the Crown Office and Procurator Fiscal Service (COPFS).

A spokesperson added: "Investigations continue and we are unable to comment further."

Mr Murrell, 59, is the husband of Scotland's former first minister Nicola Sturgeon.

He was rearrested last month and charged in connection with the embezzlement of SNP funds amid a police probe into the funding and finances of the party.

COPFS will now decide if there is enough evidence to prosecute Mr Murrell, and whether it believes a prosecution would be in the public interest.

The long-running inquiry - dubbed Operation Branchform - has been ongoing since July 2021.

The probe is linked to the spending of around £600,000 raised by SNP supporters to be earmarked for Scottish independence campaigning.

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Ex-party treasurer MSP Colin Beattie has been arrested and released as part of the probe, as has ex-SNP leader Ms Sturgeon.

Neither has been charged, and a COPFS spokesperson said investigations "remain ongoing".

Following her arrest in June 2023, Ms Sturgeon said: "The thing that sustains me right now is the certainty that I have done nothing wrong."

Mr Murrell's initial arrest in April 2023 led to a police search of his home with Ms Sturgeon. The SNP's headquarters in Edinburgh was also searched.

A spokesperson for COPFS confirmed the report had been received relating to "incidents said to have occurred between 2016 and 2023".

"Professional prosecutors from COPFS and independent counsel will review this report," the spokesperson said.

"They will make decisions on the next steps without involving the Lord Advocate or Solicitor General.

"All Scotland's prosecutors operate independently of political influence. Before deciding what action to take, if any, in the public interest, prosecutors will consider if there is enough evidence.

"There must be evidence from at least two separate sources to establish that a crime was committed and that the person under investigation was the perpetrator.

"This evaluation will involve a thorough examination of the numerous witness statements and extensive evidence collected by police.

"Prosecutors may instruct the police to conduct further investigations before taking a decision."