Belarus has denied claims by the United States that an officially sanctioned "death squad" is operating on its territory, targeting government opponents.
The claims came this week from the US State Department, which said it has "detailed and credible" evidence of the squad, obtained from high-ranking Belarus defectors.
It follows the disappearance of several high profile politicians and officials, amid reports that an elite unit, named Almaz (Diamond), is responsible. Documents backing the US claims were released this week by opposition figures in Belarus.
But Belarus has dismissed calls for an investigation.
"All these documents are false," said Mr Mikhail Myasnikovich, head of the presidential office in Minsk. "There is no death squad."
Rumours that Almaz, a squad of soldiers who wear distinctive maroon berets, are responsible for the disappearances have circulated since a former Interior Minister, Mr Yury Zakharenko, vanished two years ago while out walking his dog.
Another man to disappear was the former chairman of the elections commission, Mr Vikor Gonchar, together with his associate, Mr Yury Krasovsky.
Also missing is journalist, Mr Dmitry Zavadsky, a former personal cameraman of the president, who vanished last year.
The US says it has clear evidence, provided by two officials of the Belarus prosecutor's office who were originally detailed to investigate the case.
Washington said the men, now in hiding in the US, defected when they believed their lives were in danger after uncovering key evidence.
President Alexander Lukashenko of Belarus this week called the allegations "provocations" and accused Washington of trying to undermine his authority.
"I would advise [the US] to mind its own business and not meddle in things it does not understand," he said.
Belarus, a former Soviet republic sandwiched between Russia and Poland, already has the reputation for being one of the most repressive countries in Europe. Political opponents complain of being harassed and jailed, and the government retains a tight control over the police, media and levers of power.
Mr Lukashenko's presidency is not recognised as democratically legitimate by many European nations after allegations that a referendum to extend his tenure in office was unfair.
Many aid organisations, including the Soros Foundation, have pulled out, citing worries about human rights, and Western aid has been cut, leaving the country one of Europe's poorest.
But Mr Lukashenko received support this week from China, with President Jiang Zemin making the first visit by a Chinese president to the country and promising aid and support.