Britain says Iran's government has recently arrested several female activists as part of a campaign to stifle dissent.
The U.K. Foreign Office named photographer Maryam Majd, filmmaker Mahnaz Mohammadi, journalist Zahra Yazdani and women's rights advocate Maryam Bahrman as being among those who have been detained in the past weeks.
Foreign Secretary William Hague said in a statement released late Thursday that the women join a host of journalists, bloggers, students and human rights defenders behind bars in Iran.
Hague says that the arrests "are truly disturbing."
Iranian officials have made no comment on the arrests.
(This version CORRECTS APNewsNow. Corrects name of photographer in second paragraph. Updates with attempt to reach Iranian officials.)