A journalist with Iran's reformist Sharq daily has been arrested in Tehran.
Sadra Mohaqeq was arrested on September 19 at his home in the Iranian capital, reports said.
The reason for his arrest is not clear.
Mohaqeq was also arrested in 2013 in a crackdown on pro-reform media.
The semi-official Mehr news agency reported that Mohaqeq was arrested by a “security body."
In April, four journalists arrested in November 2015 were sentenced to between five and 10 years in prison for "colluding" with foreign governments and acting against "national security".
Media watchdogs say journalists in Iran have to work in a climate of fear and censorship.