Washington Post reporter Jason Rezaian 'held in Iran'

Jason Rezaian, a 38-year-old dual Iran-US citizen, and his Iranian wife Yeganeh Salehi, were taken into custody on Tuesday evening, the paper said.

Two freelance photographers, also US citizens, were being held too, it said.

Western news organisations, including the BBC, have great difficulty operating in Iran, with journalists facing detention and surveillance.

"We are deeply troubled by this news and are concerned for the welfare of Jason, Yeganeh and two others said to have been detained with them," Washington Post foreign editor Douglas Jehl said in a statement.

Mr Rezaian has been the Post's Iran correspondent since 2012. Ms Salehi works as a correspondent for the National, an English-language newspaper based in the United Arab Emirates.

Authorities in Iran frequently detain or harass journalists working for western news organisations, and Americans with dual citizenship are typical targets.

Iran-based family members of BBC journalists have been questioned by intelligence services, and authorities have attempted to intimidate London-based BBC Persian staff by setting up false Facebook pages on which BBC staff members purport to admit to sexual misconduct or to spying for the UK.

Last year, Iran warned the families of 15 BBC Persian Service journalists that their relatives must cease working for the BBC in London, and in some cases the lives of the staff were threatened.

In 2009, Iranian-American reporter Roxana Saberi was held for five months after being arrested for purchasing a bottle of wine. She had worked as a freelancer for the BBC and for US radio network National Public Radio. The same year, a reporter for the AFP news agency was held for several days.

BBC News