The director of a prominent Belarus opposition web site that has faced pressure from the government was found dead Friday.
Relatives found Oleg Bebenin, 36, at his dacha outside the capital, Minsk, said Natalya Radina, an editor at the web site, Charter97.org.
An autopsy has confirmed the cause of death as suicide, a spokesman for the local prosecutor's office said Saturday, Interfax reported.
No indication of a fight was found in Bebenin's house, and there were no traces of violence on the journalist's body, a regional police spokesman told Interfax.
But Bebenin's colleagues and supporters questioned the official version.
The journalist left no suicide note, said Andrei Sannikov, an opposition candidate in the 2011 presidential election who was supported by Bebenin, Interfax reported.
The journalist had no problems in the family and had shown enthusiasm about his work lately, Radina said.
"I don't believe the police's version. I don't believe Bebenin could have killed himself. I can say for sure that Oleg Bebenin had big plans," she said, Interfax reported.
Bebenin was planning to go see a film in a movie theater just hours before his death, said Mike Harris of Britain-based rights watchdog Index of Censorship, Charter97.org reported.
Charter97.org, a news web site that is critical of President Alexander Lukashenko's government, is one of the most prominent opposition media outlets in Belarus. Bebenin, a professional journalist, was one of its founders in 1998, Gazeta.ru reported.
Lukashenko, in power since 1994, tolerates little dissent, and opposition groups and critical media have faced pressure for years.
Charter97.org has faced two investigations this year over material about the Belarussian security service and the KGB, as well as a reader's published comments, Radina said.
She said authorities searched the offices and her home in the spring, confiscating eight computers, and have questioned her repeatedly in connection with the investigations.
Bebenin was abducted in 1997 and threatened by unidentified men who demanded that he stop questioning the authorities' activities, Gazeta.ru reported, adding that many opposition activists in Belarus have faced the same treatment since the country became independent in 1991.
But the journalist's death may also damage Lukashenko's reputation ahead of his bid for re-election in a vote expected to be held in February, Gazeta.ru reported, citing analysts.