Bolivia on Wednesday accused the United States of trying to “kidnap” its president, Evo Morales, after his plane was denied permission to fly over some European countries on suspicion he was taking fugitive former U.S. spy agency contractor Edward Snowden to Latin America.

Snowden was not on the plane when it landed in Vienna, an Austrian official said. The United States has been trying to get its hands on Snowden since he revealed details of its secret surveillance programs last month. Snowden is believed to be stranded in the transit lounge of a Moscow airport.

Bolivia said the incident, in which the plane was denied permission to fly over France and Portugal before making a stop in Vienna, was an act of aggression and a violation of international law.

The White House declined to comment on the Bolivian assertion.