Elizardo Sanchez said Yoani Sanchez was accompanied by her husband and another dissident blogger. Sanchez said Yoani was detained Thursday in Bayamo, where she was to blog about the trial for Spanish newspaper El Pais.
Angel Carromero was scheduled to go on trial Friday for causing a crash that killed two Cuban dissidents. Carromero was at the wheel when the car struck a tree, killing Oswaldo Paya and Harold Cepero, while Carromero and a Swedish politician, Jans Aron Modig, survived.
Paya's family has blamed the government for the crash.
Yohandry Fontana, a pro-government blogger, has said Yoani Sanchez's goal was to create a "media circus" in Bayamo.