A court in the Caspian Sea nation of Azerbaijan has arrested an opposition activist on charges of conducting illegal deals.

Natiq Cafarli's lawyer, Cavad Cavadov, said Saturday his client was arrested after he was taken in for interrogation by the country's top investigative body late Friday. Cavadov said his client has been charged with conducting "illegal business activities" and "abuse of power" but he could not immediately explain what these charges relate to.

Azerbaijani prosecutors were not available for comment on Saturday.

Cafarli is the executive secretary of the Republican Alternative opposition movement, whose leader, Ilgar Mammadov, is serving a seven-year prison term for plotting riots in 2013. International right groups, however, describe Mammadov as a prisoner of conscience.