Reporters Without Borders, RSF, has criticized the detention of the deputy editor of a reformist daily newspaper in Iran.

Iranian journalist, Sasan Aghaei of Etemad was arrested at his office on Saturday evening, August 12.

On Sunday, August 13, RSF in its Twitter page noted, “Arresting a journalist who is critical is a blatant violation of press freedom and it is a threat against all journalists.”

The charges against Aghaei, are not clear. The paper he works for is considered a reformist publication critical of hardliners.

The opposition site Kalameh reports that Aghaei was taken away by security forces on the afternoon of August 12 from Etemad’s offices of in the Iranian capital.

Later, they searched Aghaei's home andransferred him to Tehran's Evin prison, the report said.

Aghaei has been arrested several times in the past, including in the 2009 state crackdown that followed the disputed reelection of former President Mahmud Ahmadinejad.

The Paris-based media watchdog Reporters Without Borders says Iran is one of the world’s five biggest prisons for media workers.

Earlier this month, the group said 10 journalists and 17 citizen journalists are currently detained in Iran.