Saudi Arabia on Thursday temporarily released from custody at least four women’s rights advocates, according to a London-based Saudi human rights group and other activists.  

The four are among a group of 11 female activists on trial in Riyadh, the Saudi capital, on charges related to their advocacy for greater freedoms for women in the kingdom. Saudi authorities began arresting the women about a year ago in a dragnet that was strongly criticized by human rights groups and was part of a crackdown on perceived enemies and opponents by Crown Prince Mohammed bin Salman. 

ALQST, a London-based human rights group, identified the detainees released Thursday as Hatoon al-Fassi, Amal al-Harbi, Maysaa al-Manea and Abeer Namankani. Three other women who are defendants in the same trial were released in March. 

The fate of several other female activists and male supporters who have been detained remains unclear.   

Many of the women said they were tortured while in custody — an allegation that shocked many Saudis and intensified international criticism of the Saudi leadership. Saudi authorities have denied torturing prisoners. 

The prominence of some of the detainees has also sparked outrage. In a March letter protesting the arrest of Fassi, a professor of women’s history, the Middle East Studies Association of North America noted that she was a “renowned historian of pre-Islamic Arabia” who was “widely respected internationally by her colleagues and the many younger scholars she has mentored.” Her arrest, the letter added, was a “travesty of justice.”