The Scottish government marked International Women’s Day on Tuesday by issuing a formal apology to women who were wrongfully accused of practicing witchcraft hundreds of years ago.

Between the 16th and 18th centuries, approximately 4,000 people were accused of witchcraft, according to the group Witches of Scotland, which has been campaigning for the apology.

In total, more than 2,500 people were executed, four-fifths of them women. They were mostly strangled and then burned, after making confessions that were often extracted under torture.

"People would take turns interviewing them, keep them awake for days and days and days, and ask them about witchcraft," Claire Mitchell, founder of Witches of Scotland, told Agence France-Presse (AFP).

Addressing Scottish lawmakers, First Minister Nicola Sturgeon said it was "injustice on a colossal scale" that was "driven at least in part by misogyny in its most literal sense – hatred of women."

"At a time when women were not even allowed to speak as witnesses in a court, they were accused and killed, because they were poor, different, vulnerable or, in many cases, just because they were women," she said.

"I am choosing to acknowledge that egregious, historic injustice and extend a formal posthumous apology to all those accused, convicted, vilified or executed under the Witchcraft Act 1563."

Witch hunts were enthusiastically promoted by Scotland's King James VI, who became also King James I of England in 1603.

His obsession found voice in William Shakespeare's "Scottish play," featuring three witches who lead Macbeth to his doom.

The victims were forced to confess that "they were dancing with the devil, having sex with the devil," Mitchell said.

"And those confessions were used by the courts in Scotland ... to prosecute these women for witchcraft."

They are recognized in the windblown 16th-century cemetery by a small column nicknamed the "Witches' Stone."

Passers-by often leave flower petals and coins as a tribute to those executed, including Grissel Jaffray, strangled and burnt in 1669.

In a city center street, a mosaic depicting a cone of flames commemorates Jaffray, the woman known as "the last witch of Dundee."

Sturgeon noted some critics had queried the point of an apology centuries later but said: "it might actually be pertinent to ask why it has taken so long."

"Acknowledging injustice, no matter how historic, is important," she said.