The Iranian authorities should release the three journalists and a fourth person who are still being held a week after their detention, says Human Rights Watch (HRW).
There has been no response to previous calls to free the four, as I reported last Friday, who are being held incommunicado.
They are Jason Rezaian, the Washington Post's correspondent who has dual Iranian and American nationality, his journalist wife, Yeganeh Salehi, and two unnamed people, a photojournalist and her spouse.
Mary Breme Rezaian, Jason's mother, told HRW that "agents" arrested the quartet at her son's home on the night of 22 July. Iranian authorities have not said where they are holding the four or disclosed the legal basis for their detention.
Swiss consular officials, who represent US interests in Iran, have not been allowed to visit them.
Iranian security officials have also summoned for questioning, or arrested, at least seven other journalists in the past two months.
Source and more information: HRW
