She is in custody and was being questioned, Police Scotland said in a statement on Twitter.
The police investigation is looking at what happened to more than 600 000 pounds raised by Scottish independence campaigners in 2017, which was supposed to have been ring-fenced but may have been used for other purposes. In April, Sturgeon's husband, Peter Murrell and the party's then treasurer were both arrested and then released without charge pending further investigation as part of the same inquiry.
Sturgeon announced her resignation as Scottish first minister in February, saying her dominance over her party and the country was no longer the asset it once was in the fight for an independent Scotland. In power since 2014, she said she had become too divisive - and too tired - to reach across the political divide, and she wanted to step away from the"brutality" of modern politics to focus on"Nicola Sturgeon the person".In times of uncertainty you need journalism you can trust. For 14 free days, you can have access to a world of in-depth analyses, investigative journalism, top opinions and a range of features. Journalism strengthens democracy. Invest in the future today.