Amnesty International has urged Houthi rebels who control Yemen's capital and other parts of the country to release 27 members of the minority Baha'i faith they detained on 10 August.
The Baha'is remain in the national intelligence agency’s custody without access to lawyers or family visits a week after their arrests at a youth workshop in Sanaa, Amnesty said on Wednesday.
The rights group called the arrests "a blatant case of persecution of a minority faith".
A total of 65 people including 14 women and minors were initially held without an arrest warrant. Some were later released while further arrests were made on Tuesday, according to Amnesty.
“The arbitrary arrests of Baha'i people for doing nothing more than attending a peaceful community event is completely unjustifiable," said Amnesty's Middle East and North Africa Programme deputy director Magdalena Mughrabi.
“The Houthi must end their harassment of minorities and respect the right to freedom of religion - a right that is enshrined in the country’s own constitution and international law.”
Amnesty said the detentions appear to be part of a wider crackdown against the Baha'is, who were also persecuted under ex-president Ali Abdullah Saleh before the current armed conflict broke out in 2014.
On 25 September, Baha’i prisoner Hamed Haydara is due for his final court hearing after he was detained in December 2013 for trying to convert Muslims to the Baha’i religion, a capital offence under Yemeni law, Amnesty reported.
Haydara is also charged with apostasy, spying for the Israeli government and 'undermining the independence of the Yemeni State', all of which carry a death sentence under Yemen's penal code, Amnesty said.
Around 250 Baha'is are believed to be living in Yemen. They have also been targeted in Iran, where the religion began in 1817.
The Houthis belong to the Zaidi sect – an offshoot of Shia Islam - and make up around one-third of Yemen's population.
Houthi rebels are supported by renegade troops loyal to Saleh, also a Zaidi, whose 33-year rule ended in 2012 after a deadly year-long revolt.
