Iranian authorities arrested an outspoken pro-reform activist, saying he conspired to act against state security, semi-official media in Iran reported Saturday.

The arrest is the latest in a wave of detentions against the backdrop of escalating tensions with the West and Tehran’s rapid advancement of its nuclear work, while talks to revive the landmark 2015 atomic accord remain at a standstill.

The semi-official Fars news agency said activist Mostafa Tajzadeh was taken into custody on Friday afternoon and charged with “gathering (to protest) and conspiracy to act against the country’s security.”

Tajzadeh is a well-known activist who has criticized the country’s top leader and high-ranking officials. He spent years in prison following the disputed 2009 re-election of Iran’s hard-line President Mahmoud Ahmadinejad and the turmoil that ensued.

Meanwhile, Tehran chief prosecutor Ali Salehi was quoted by the judiciary’s Mizan news agency on Saturday as endorsing the latest arrests and saying that activities of those detained “created divisions” that led to “incitement in the media and society.”

On Friday, the state-run IRNA news agency reported the arrests of two filmmakers over an appeal they posted on social media, accusing them of links with opposition groups based outside the country and plotting to undermine state security.

Award-wining filmmaker Mohamad Rasoulof and colleague Mostafa Al-Ahmad were taken into custody for posting a statement on social media urging members of the Iranian security forces to lay down their weapons. At least 70 Iranian filmmakers and movie industry workers had signed the appeal.

The hashtag #put_your_gun_down is a reference to the violent crackdown during the unrest following a building collapse in the southwestern city of Abadan that killed at least 41 people earlier this year. The May 23 collapse dredged up painful memories of past national disasters and triggered protests in Abadan during which police clubbed demonstrators and fired tear gas.

Over the past months, there have been protests in Iran over price hikes and the slashing of subsidies by the government. Also, teachers gathered for weeks, demanding better pay and working condition.

Memories are also fresh of Iran’s fuel price hike in November 2019, when widespread protests — the most violent since the creation of the Islamic Republic in 1979 — rocked the country.

Iran has also detained a number of Europeans in recent months, including two French citizens and a Swedish tourist, as it seeks to gain leverage in the nuclear negotiations.

Dual nationals and those with Western ties have also been arrested, often on widely criticized espionage charges, to be used as bargaining chips in the negotiations. Tehran denies using detainees to further its political aims.

Talks to revive Tehran’s tattered nuclear deal with world powers have stalled for months. A recent effort to break the deadlock between U.S. and Iranian negotiators ended without making progress in Qatar.

(AP)