Committe to Protect Journalists will be collecting signatures until 31 July on a Facebook petition in support of Maziar Bahari, Newsweek’s Tehran correspondent, who is being held without charge in Iran.

Bahari, who is also an internationally acclaimed filmmaker, was detained on 21 June as part of Iran’s post-election crackdown on the media. More than 100 prominent journalists from around the world signed a letter calling for Bahari’s release on 15 July.

You can sign the Facebook petition here. Please remember to ask your Facebook friends to sign as well.