Victor Gonchar, the deputy speaker of the parliament that President Lukashenko disbanded in 1996, has not been seen since 16 September, when he went to a steam bath in the Belarus capital of Minsk.
His wife said he telephoned from the sauna, saying he would be home, but he failed to turn up. With him at the baths and also missing is Anatoly Krasovsky, a publisher.
The men are not the only people to have disappeared in Belarus, a former Soviet republic that President Lukashenko rules with an iron grip. The former chairwoman of the Central Bank, Tamara Vinnikova, went missing in April and the former interior minister, General Yuri Zakharenko, disappeared in May.
"We call on the government of Belarus to do everything in its power to locate Mr Gonchar, Ms Vinnikova and General Zakharenko," the US State Department spokesman said. Amnesty International said it feared that Mr Gonchar and the others might be "in incommunicado detention, where they will be at risk of torture, ill- treatment or possible disappearance (death)".
President Lukashenko, who has expressed admiration for Hitler, is popular with many in Belarus, who say he has saved them from the chaos experienced by Russia's attempts at reform. By "popular request" President Lukashenko extended his rule to 2001. Mr Gonchar angered him by organising an unofficial presidential election in July.Reuse content