Armed men detained prominent Sudanese women's rights campaigner Amira Osman in a nighttime raid on her home in Sudan's capital Khartoum, her sister said on Sunday.
Osman's detention comes after what activists say has been a campaign of arrests of civil society and pro-democracy figures since a military takeover in October.
The United Nations mission in Sudan said on Twitter it was outraged by Osman's arrest, citing a "pattern of violence against women's rights activists" that risked reducing their participation in politics.
Sudanese security officials did not immediately respond to a request for comment.
Some high profile political figures have been released since the Oct. 25 coup, but activists say others have remained in detention and arrests have continued.
About 15 armed, masked men wearing civilian clothes abducted Osman after storming her house in Al Riyadh neighbourhood late on Saturday night, her sister Amani Osman told Reuters.
"We don't know where she is or the security agency that took her. We are worried about the nature of her arrest and her critical health condition," she said, adding that Osman had been partially paralysed in an accident some years ago.
Osman campaigned for women's rights in Sudan under the Islamist rule of former President Omar al-Bashir, who was ousted during an uprising in 2019.
She was arrested in 2013 under public order laws for refusing to wear a headscarf, and was convicted and fined in 2002 for wearing trousers.
Women played a prominent role in the protests that led to Bashir's overthrow. A transitional government later repealed the public order law used to regulate women's dress and behaviour, though some other restrictive laws remained.
(Reporting by Khalid Abdelaziz; Writing by Aidan Lewis; Editing by Alexander Smith)