Stock Photo - An exhibition organised by Greenpeace on a ship anchored on the Vltava River in Prague on October 5, 2013 points to their colleagues arrested in Russia over alleged piracy and asks the visitors to sign a petition, send a letter to the Russian ambassador or a message to the arrested activists. Prague Czech Republic (CTK Photo/Michal Krumphanzl)

Stock Photo: An exhibition organised by Greenpeace on a ship anchored on the Vltava River in Prague on October 5, 2013 points to their colleagues arrested in Russia over.