"In war, truth is the first casualty," said Greek tragic dramatist Aeschylus more than 2,500 years ago. This apparently still holds true in the current Ukraine conflict: each side is proclaiming its intention to avoid war, yet clamors in the battle to control the interpretation of events. Even expert observers are finding it difficult to separate propaganda from fact.

In the past days and weeks there have been contradictory reports about the activities of Russian soldiers and intelligence agents in eastern Ukraine. A few days ago, the Ukrainian government showed the Organization for Security and Cooperation in Europe (OSCE) photographs said to prove that some of the armed fighters in the region actually belong to the Russian military or intelligence services. The photos showed a man with a long beard who is said to have appeared on other pictures from Georgia in 2008 - as a Russian underground fighter. The Ukrainian government sent the images to the media via Twitter and other channels.

Jen Psaki, a spokeswoman for the US State Department, called the photos "a further indication of the link between Russia and the armed militias in eastern Ukraine." The pictures certainly support the version repeated by Washington and Kyiv for the past few weeks: that some of the fighters on the ground are Russian military units and that Putin is continuing the game that he played in Crimea. Russian Foreign Minister Sergey Lavrov, meanwhile, has repeatedly denied the allegations, maintaining that Russia has not sent any troops into Ukraine.

Psaki maintains that the Kremlin is linked to the separatists in Ukraine

Fabricated evidence

A journalist for Time magazine later found the bearded fighter, Alexander Mozhaev, in the eastern Ukrainian town of Slovyansk. He readily agreed to an interview and appeared highly amused at the notion that he was thought to be a Russian agent. He said that though he was Russian, he had never been to Georgia, and that he was drawn to Ukraine by a mixture of adventure-lust and nationalism. He even showed the reporter his passport.

When sources - be they governments, analysts, or eyewitnesses - are inaccurate, it's vital that the press undertake critical research - though that is extremely difficult in an armed conflict. "The big challenge for the media and its users is to bring light into the fog of propaganda," says Hanno Gundert, head of the n-ost network, which provides independent reporting on Eastern Europe. For the population of Russia, however, this is now virtually impossible, he says.

War of small words

Mozhaev was amused by suggestions he was a Russian agent

Many broadcasters take sides deliberately in their choice of words. While Western and Ukrainian media usually talks about Kyiv's "interim government," pro-Kremlin Russian media outlets such as Russia Today routinely brands it a "putsch government." The man that one side calls a "self-proclaimed mayor," is dubbed a "mayor of the people" by the other side. Such nuances steer opinions, just as the choice of subjects and the experts quoted do. "The reception of different sources is central," says Gundert. He argues that Ukraine's media landscape is more diverse than Russia's, not least because the Maidan movement has fostered more critical reporting.

But the Russian-speaking population in Ukraine generally gets its information from the Russian media. And that is - except for very few exceptions - in line with the Kremlin. "Russian TV has not carried professional journalism for some time now," says Tatiana Felgengauer, deputy editor-in-chief at the Echo of Moscow broadcaster, sometimes called the last bastion of a free press in Russia. She argues that the Kremlin is trying to establish a one-sided view via state TV station: "The fascists are in Kyiv, and our friends are in eastern Ukraine."

Moscow's strategy has apparently been successful in Russia, Crimea, and parts of eastern Ukraine. For that reason, Gundert is unsurprised by how much support Putin enjoys in Russia: "It's important to make clear how difficult it is get out of the media bubble there."