PARIS (AP) – Iranian authorities have arrested at least 24 journalists and bloggers since postelection protests began a week ago, and a media watchdog says reporters are a “priority target” for Iran’s leadership.

Among those detained were the head of the Association of Iranian Journalists and a Canadian reporter for Newsweek. The British Broadcasting Corporation’s correspondent has been ordered to leave the country.

Newsweek said in a statement later that its correspondent Maziar Bahari, a Canadian citizen, was detained without charge Sunday morning and has not been heard from since. Newsweek defended his coverage of Iran as “fair and nuanced” and called for his release.

In most cases, the reasons behind the detentions remain unclear.