Iran is said to be rounding up thousands after crushing bloodiest unrest in years
Security forces reportedly use unofficial warehouses and secret lock-ups as activists say arrests stand at more than 42,000

Plain clothes Iranian security forces have rounded up thousands of people in a campaign of mass arrests and intimidation to deter further protests after crushing the bloodiest unrest since the 1979 Islamic Revolution, sources told Reuters.
Modest protests that began last month in Tehran’s Grand Bazaar over economic hardship unleashed long-suppressed wider grievances and swiftly escalated into the gravest existential threat to Iran’s Shiite theocracy in nearly five decades, with protesters commonly calling for ruling clerics to step down.
Authorities cut internet access and stifled the unrest with overwhelming force that killed thousands, according to rights groups. Tehran blames “armed terrorists” linked to Israel and the United States for the violence.
Within days, plain clothes security forces launched a campaign of widespread arrests accompanied by an intensified street presence based around checkpoints, according to five activists who spoke on condition of anonymity from inside Iran.

They said detainees had been placed in secret lock-ups.