RFE/RL's Azerbaijani Service reports that human rights activist Intigam Aliyev has been detained in Baku.
A court in Baku charged Aliyev on August 8 with tax evasion, abuse of office and illegal entrepreneurship.
His lawyer, Anar Gasymly, said a court swiftly jailed Aliyev for three months.
Aliyev has denied the allegations and said that his arrest is politically motivated.
Aliyev is a veteran rights activist and was awarded the Homo Homini human rights award in the Czech Republic in 2013.
Czech NGO People in Need said, "It is shocking that this is all happening as Azerbaijan is heading Europe's top rights watchdog -- the Council of Europe."
Aliyev is the latest rights defender to be detained in Azerbaijan.
Rasul Jafarov was detained on August 2 for alleged tax evasion and abuse of authority.
Leyla and Arif Yunus are also in custody after being arrested on charges of treason, tax evasion, and illegal entrepreneurship.