Source: Sky News
Nicola Sturgeon's husband, Peter Murrell, has been arrested in connection with an investigation into the funding and finances of the Scottish National Party (SNP).
The former SNP chief executive is in custody and is being questioned by detectives.
Police Scotland said a 58-year-old man was arrested as part of an ongoing investigation.
Officers are also carrying out searches at a number of addresses, the force added.
A large police tent has been set up outside the couple's Glasgow home - while officers have also been seen at the SNP's headquarters in Edinburgh.
Police Scotland has been investigating the spending of about £600,000 which was earmarked for Scottish independence campaigning.
The SNP said in a statement: "Clearly it would not be appropriate to comment on any live police investigation but the SNP have been co-operating fully with this investigation and will continue to do so.
"At its meeting on Saturday, the governing body of the SNP, the NEC, agreed to a review of governance and transparency - that will be taken forward in the coming weeks."
A spokesperson for the Crown Office and Procurator Fiscal Service said: "COPFS will continue to work with the police in this ongoing investigation.
"It is standard practice that any case regarding politicians is dealt with by prosecutors without the involvement of the Law Officers."
It comes just a week after Humza Yousaf was legally sworn in as Scotland's sixth first minister - replacing Ms. Sturgeon after her shock resignation in February.
The SNP's political opponents have called for full transparency from Mr. Yousaf and Ms. Sturgeon.
Scottish Labour deputy leader Jackie Baillie said: "This is a deeply concerning development and the Police Scotland investigation must be allowed to proceed without interference."
She added: "We need Humza Yousaf and Nicola Sturgeon to urgently state what they knew and when."
Ms. Sturgeon was asked by Sky's political editor Beth Rigby last month whether the ongoing investigation into SNP finances - and the pressure on her and her husband as a result - had played a part in her departure.
The former Scottish first minister and SNP leader replied: "No, it hasn't. No."
