Police Scotland, the national force, said in a statement that a 52-year-old woman was “arrested” and was being held for questioning. The BBC and a spokesperson for the former leader confirmed that it was Sturgeon who was detained.
She served as first minister for eight years before her sudden resignation earlier this year.
Sturgeon’s husband, Peter Murrell, was taken in for questioning in April and released without charge. Police have searched the pair’s home in Glasgow, as well as the party headquarters.
Some members of her party, including its former treasurer, Colin Beattie, have been taken into custody by Police Scotland and later released.
When Sturgeon announced her resignation in February, she cited concerns about her role as a polarizing figure in a nation divided over its future. She spearheaded an ultimately unsuccessful campaign for Scotland’s independence from the United Kingdom.
Her move to step down sparked a race for succession among key party leaders, with Humza Yousaf assuming the position.