The plain-clothes agents, he says, shackled him and drove him blindfolded to a local intelligence detention center. There, he says, they beat him with an iron bar, breaking bones and damaging his left ear and right eye.

Hamid says the authorities accused him of spreading propaganda against the regime and contacting opposition groups outside Iran. The evidence? His own phone calls.

"They said, ‘On this and this day you spoke to such and such person,'" says Hamid, now 30 and a human rights activist in Sweden. "They had both recorded it and later they also showed me the transcript."