Ferghana.ru, which is registered outside Uzbekistan to avoid heavy censorship, quoted an unnamed relative of Umarov as saying he was released on Saturday. “He is in a safe place,” the relative was quoted as saying.

Neither the Uzbek government nor the U.S.-based public relations company hired by Umarov’s supporters could be reached for comment.

Following a string of 2003-2005 “colour revolutions” in Georgia, Ukraine and Kyrgyzstan, businessman Umarov founded the Sunshine Uzbekistan Coalition, a movement that called for reforms in the authoritarian state.

In 2005, he was arrested on embezzlement and tax evasion charges and in 2006 a court sentenced him to 10 years in jail. Umarov has denied any wrongdoing.

Uzbekistan was extremely isolated when Umarov was arrested amid Western condemnation of the government’s suppression of May 2005 unrest in the town of Andijan where witnesses say hundreds died.

Relations have improved since. Uzbekistan has allowed the transit of nonlethal supplies to U.S. troops in Afghanistan and the European Union recently dropped sanctions introduced after the Andijan clashes.

Uzbekistan is due to hold parliamentary elections in December.