The recent wave of arrests of journalists and bloggers in Iran is a worrying sign of a government crackdown ahead of parliamentary elections in March.
Parastoo Dokouhaki a journalist and women's rights activist, who was one of the first women bloggers in Iran, and journalist Marzieh Rasouli were arrested on 15 January, just one week after two other journalists, Fatemeh Kheradmand and Ehsan Houshmandzadeh were detained.
Today, it has been reported that another reformist journalist Saeed Razavi Faqih was also detained on arrival in Tehran from France.
Human rights campaigners claim the arrests reflect the government's concern that the 2 March elections could spark fresh protests like those that took place in the wake of the 2009 presidential elections.
Hadi Ghameni, executive director of the International Campaign for Human Rights in Iran, said the recent arrests indicate that the government is aware of the "resilient popularity" of the Green Movement. It is preemptively imprisoning journalists and bloggers, irrespective of whether they are currently involved in politics, he said.
"They are intimidating dissidents not to dare to get mobilised and pre-emptively putting many journalists and online writers, relevant or irrelevant to political activism, behind bars to prevent potential of re-emergence of a protest movement."
Dokouhaki, whose blog Zan Nevesht or "Written by a Woman" was awarded Best Blog by an Iranian journalist by Deutsche Welle, has not been involved in politics or activism for the past three years and has been treated for depression following her father's death.
Around 80 women's rights activists have been arrested since 2009 in Iran and it was estimated in June last year that at least 34 were being held in Tehran's notorious Evin prison. Their arrests were part of a wider campaign against the Green Movement and its potential allies following the 2009 election.
According to figures released by the Committee to Protect Journalists last year, Iran already has the worst record for imprisoning journalists, with 42 behind bars.
Ghameni said he feared a "fresh wave" of arrests appeared to be just starting: "It certainly demonstrates extreme nervousness of security and intelligence forces over losing control during upcoming elections," he said.
The crackdown comes amid vicious infighting between conservative camps in the run-up to the elections, which reformist political parties have already boycotted. The government also faces deepening economic pressures that are likely to worsen following the announcement by the European Union of a ban on all new oil contracts in a growing row over the country's nuclear programme.
Network problems and restricted access to social media sites such as Twitter also suggest the government is also seeking to prevent the internet being used to fuel protests in a repeat of 2009.
The government has imposed new rules on Iran's Internet cafes and, inspired by China's internet restrictions, also appears to be pushing ahead with plans to launch a domestic network that it intends to replace the global web.