New Delhi, Jan. 14 -- They are shown handcuffed, their faces blurred. The confession videos, broadcast on Iranian state media, feature dramatic background music interspersed with clips appearing to show protesters attacking security forces. Some showcase gruesome homemade weapons that authorities claim were used in the attacks. Others highlight suspects in grainy security footage, appearing to set fires or destroy property.

Iran alleges these confessions, which often include references to Israel or America, are proof of foreign plots behind Iran's nationwide protests. Activists say they are coerced confessions, long a staple of Iran's hard-line state television, the only broadcaster in the country. And these videos are coming at an unpre...