Former Scottish leader Nicola Sturgeon arrested amid fiance probe

Former leader of the Scottish National Party (SNP) Nicola Sturgeon was arrested on Sunday as part of an investigation into financial irregularities, according to police and UK media.

"A 52-year-old woman has today been arrested as a suspect in connection with the ongoing investigation into the funding and finances of the Scottish National Party," police in Scotland said in a statement, with British media confirming her identity as Sturgeon.

The woman is being questioned by detectives while she is being held by the police, they added.

The third arrest in the investigation has shocked Scotland's political establishment.

Sturgeon's husband, Peter Murrell, the former chief executive of the Scottish National Party (SNP), was arrested as part of the probe in April.

Murrell has long faced questions over the alleged diversion of £600,000 ($750,000) in SNP donations that were meant to support its drive for Scottish independence, AFP reported.

In addition, it was noted that he failed to disclose a personal loan to the SNP of more than £100,000, which would have violated laws governing the transparency of political fundraising.

He was later released without charge pending further investigation. Meanwhile, party treasurer Colin Beattie was also arrested in April and later released.

Moreover, Sturgeon made her final appearance as First Minister in the Scottish Parliament in March, having announced her intention to retire a month earlier.

Sturgeon succeeded Alex Salmond as first minister of Scotland in the wake of the independence referendum in 2014, a position she held for more than eight years. She was also the longest-serving female minister in Scotland.