SWISS officials foiled an apparent spying operation by Russians reportedly posing as plumbers in Davos.
They were said to have concluded the pair were employed by the Kremlin to record and tap into the conversations of important figures at the World Economic Forum.
The two men were picked up at the exclusive resort in August after they aroused suspicion by staying for an unusually long time.
The report in the newspaper said the two Russians were checked by Swiss police in August last year in the ski resort, which is hosting the gathering of the global business and political elite this week.
The pair presented diplomatic passports and left the country, the paper said.
Police in the eastern Swiss canton of Grisons said two men with Russian diplomatic passports had been the subjects of a routine identity check in Davos in August 2019, but no connection had been established between their visit and the World Economic Forum.
SPY SUSPECTS HAD DIPLOMATIC PASSPORTS
A police spokeswoman said: "It is true that we checked two Russian citizens in Davos and they identified themselves with diplomatic passports, but we could not ascertain any reason to detain them.
"They were allowed to go."
A spokesman for the Russian embassy in Bern dismissed the report, saying two of its diplomats accredited outside Switzerland had been checked and allowed to go on their way.
He said: "Diplomatic passports are given to high-ranking officials, not to manual labourers.
"I think this was probably a dumb joke."
MOST READ IN NEWS
Maria Zakharova, a spokeswoman for the Russian Foreign Ministry in Moscow, said she was not aware of the incident.
Investment fund manager Bill Browder, who has led a campaign to expose corruption and punish Russian officials whom he blames for the death of his lawyer, Sergei Magnitsky, who died in a Moscow prison in 2009 after complaining of mistreatment, said the alleged incident showed the reach of the Russian state.
Mr Browder told Reuters in Davos: "The Russians are actively targeting all of their enemies in all different countries — they have huge resources and Davos is an important place, and this is the one place I can come and personally challenge Russian officials over the murder of Sergei Magnitsky.”
Russian prosecutors have said they suspect Mr Browder of ordering a string of murders, including of Magnitsky, in a twist the financier has dismissed as ludicrous.