LONDON (Reuters) - Iran has "dramatically escalated" a crackdown on dissent in the run-up to this week's parliamentary elections, arresting lawyers, students and journalists and targeting electronic media, human rights group Amnesty International said on Tuesday.
"In Iran today you put yourself at risk if you do anything that might fall outside the increasingly narrow confines of what the authorities deem socially or politically acceptable," said Ann Harrison, an Amnesty Middle East expert.
"Anything from setting up a social group on the internet, forming or joining an NGO (non-governmental organization), or expressing your opposition to the status quo can land you in prison," she said in a statement.
Friday's election is the first nationwide vote since the disputed 2009 re-election of President Mahmoud Ahmadinejad that sparked eight months of unrest and a crushing state response.
The vote is likely to highlight the popularity of the clerical establishment as it stands firm against Western pressure to curb its nuclear work.
Amnesty said in a report that Iranian authorities had steadily cranked up repression of dissent in the last year, launching a wave of arrests in recent months.
The arrests have targeted a range of groups, including lawyers, students, journalists, political activists and their relatives, religious and ethnic minorities, filmmakers, and people with international connections, it said.
Amnesty said the crackdown "laid bare the hollowness of Iran's claims to support protests in the Middle East and North Africa."
The clampdown has targeted electronic media, seen by Iranian authorities as a major threat, the rights groups said.
In January a senior police officer called Google an "espionage tool", not a search engine, it said.
Also last month, the new "cyber police" ordered owners of Internet cafes to install closed-circuit television and to register the identity of users, Amnesty said.
Millions of Iranians have experienced disruption to email and Internet access in the run-up to the election, including problems accessing websites via virtual private network software which many in Iran use to get around government filters.
Blogger Mehdi Khazali was sentenced to four-and-a-half years in prison this month after being charged with "spreading propaganda against the system", Amnesty said.
The rights group urged other countries not to allow tensions over Iran's nuclear program to distract them from pressing Iran to live up to its human rights obligations.
Leading reformist candidates have refused to stand in Friday's vote, leaving rival hard-line factions of the Supreme Leader, Ayatollah Ali Khamenei, and Ahmadinejad to battle it out.
Leaders of Iran's pro-reform opposition have been sidelined since the 2009 vote, with two of them, Mirhossein Mousavi and Mehdi Karoubi, under house arrest since February 2011.
Mousavi and Karoubi both lost to Ahmadinejad in the 2009 vote and insist it was rigged to secure his re-election.
(Reporting by Avril Ormsby; Editing by Rosalind Russell)