Iranian security forces arrested prominent human rights lawyer Nasrin Sotoudeh on Wednesday, her husband said in a Facebook post.
"A few hours ago Nasrin was arrested at home and sent to the court at Evin," Sotoudeh's husband Reza Khandan wrote. "I once told investigators in the investigation room: 'Of all the things that a government must do for its country, you only know one, arresting people.'"
Khandan did not say what charges Sotoudeh may face.
Arbitrary detentions are common within Iran's opaque judicial system. Many political prisoners are kept in solitary confinement and not allowed to see their families for long periods, according to human rights groups. Iran also has one of the world's highest rates of capital punishment.
Iranian judiciary officials say it is their duty to uphold the country's Islamic values as codified in Iranian law.