Moscow: Countries often issue travel advisories warning citizens of danger abroad: war, for instance, or a terrorist threat or an outbreak of disease. The Russian Foreign Ministry posted advice of a somewhat different nature on Monday, cautioning people wanted by the United States not to visit nations that have an extradition treaty with it.

"Warning for Russian citizens travelling internationally," the Foreign Ministry bulletin said. "Recently, cases of detentions of Russian citizens in various countries at the request of American law enforcement, with the goal of extradition and legal prosecution in the United States, have become more common."

Dmitry Ustinov is suspected by the US of conspiracy in smuggling night vision devices from the US and money laundering. Credit:Irina Pavlova/RIA Novosti

Citing examples in Costa Rica, the Dominican Republic, Latvia and Spain, the Foreign Ministry said, "Practice shows that the legal processes against those who were in fact kidnapped and taken to the United States carry a biased character grounded on a shaky base of evidence and having a sharply expressed inclination toward guilt."

Extradition has frequently been a contentious issue between Russia and the United States, but the disagreements have been particularly sharp in recent months over the case of Edward J. Snowden, the fugitive former intelligence contractor who is wanted on criminal espionage charges but has been granted temporary asylum in Russia.