Saudi security forces detained Al Nafjan in the middle of May 2018 alongside at least six other people associated with the women’s rights movement who campaigned for an end to Saudi Arabia’s ban on women driving, according to the The Washington Post, BBC Arabic, and other news outlets. The Gulf Center for Human Rights reported that Al Nafjan was detained on May 17. According to an AP report at the time, Al Nafjan and the other detainees were not allowed access to lawyers, and their whereabouts are unknown. An official statement from the Saudi State Security Presidency, which oversees domestic and international security forces, did not name Al Nafjan or any other detainee but confirmed that authorities had detained seven people for undermining the kingdom’s stability with financial assistance from abroad and for subverting national and religious traditions. The State Security Presidency also said that investigations are underway to identify additional people involved, according to the statement. The newspaper Okaz, one of the kingdom’s more liberal, privately owned pro-government papers, ran a full-page graphic repeating language from the State Security press release showing photos of Al Nafjan and the other arrested activists with the word "traitor" stamped over each of their faces. In February 2008, Al Nafjan started the blog, Saudiwoman’s blog that features her reporting and opinions on the campaign to end the ban on women driving in the kingdom, as well as coverage of other women’s rights issues, local elections, the Saudi anti-terror law, and profiles of Saudi human rights activists. Al Nafjan’s reporting included op-eds and analysis of women’s rights movements in Saudi Arabia, feminism in Saudi society, reform movements and protests in the kingdom, and education and textbook standards put forth by the Saudi Ministry of Education. She contributed opinion pieces to CNN, Foreign Policy, Newsweek, and the Guardian. Al Nafjan’s last published writing on her blog was September 2017. In the same month, authorities under Crown Prince Mohammed bin Salman began an ongoing wave of arrests of perceived dissidents–including journalists, academics, religious figures, and activists–that has targeted those who were previously critical of the Saudi government, as well as independent thinkers and writers who did not publicly state their support for the crown prince or his policies. In her role as an activist, Al Nafjan took part in the campaign to end the driving ban, including by publicly driving a car in defiance, according to the Gulf Center for Human Rights. Al Nafjan’s arrest also came as part of a broader wave of arrests aimed at activists who campaigned against the ban on women driving. Beginning in May 2018 and continuing since, Saudi authorities began detaining prominent figures in the movement, even as Crown Prince Mohammed lifted the ban on June 24, 2018. As of late 2018, authorities had not publicly disclosed any charges against Al Nafjan. Human Rights Watch reported that she potentially faces charges of undermining the security and stability of the state and suspicious contact with foreign parties, which could carry a sentence of 20 years in prison. In November 2018, Human Rights Watch and the Washington Post both reported that Saudi authorities tortured at least three of the women detained in the wave of arrests with electric shocks and floggings, and that at least one of the women tried to commit suicide in detention. According to The Wall Street Journal, at least one of the women in Saudi custody was sexually assaulted. The Wall Street Journal also named Al Nafjan specifically as one of the detainees who had been subject to abuse, without specifying what type of abuse she faced.