A business card brandished by pro-Russian separatists in eastern Ukraine as proof that a deadly attack on their checkpoint was the work of ultra-nationalists quickly became an object of derision on the Internet. Following the attack on a pro-Russian checkpoint near the flashpoint town of Slavyansk, the self-proclaimed mayor, Vyacheslav Ponomaryov, presented a business card to the international press which he said was proof of the involvement of the ultra-nationalist group Pravy Sektor ("Right Sector"). The red and black card purportedly belonged to Dmytro Yarosh, leader of the group, and was allegedly found in a burned-out car near the site of the attack, in which at least two pro-Russian rebels were killed on Sunday. But many pro-Western Ukrainians found it difficult to take the claim seriously. Within hours, a spate of mocked-up images had appeared, and a hashtag in Ukrainian meaning "Yarosh business card" was trending on Twitter. Among the hastily assembled photo montages: German Chancellor Angela Merkel pointing to one of the cards poking out of Russian President Vladimir Putin's top pocket. Another showed Stalin, Roosevelt and Churchill each with one of the cards at the Yalta Conference of 1945, which took place on the Crimean peninsula. Or there's Adam and God with the card between their outstretched arms on Michelangelo's Sistine Chapel ceiling. - 'Propaganda worse than Nazis' - The pro-Western site Ukrainian Pravda listed a few of its favourite tweets on the subject, including: - "Found Yarosh's business card at the site of Christ's crucifixion." - "It wasn't an asteroid that killed the dinosaurs, it was Yarosh's business card." - "During the assassination of Osama bin Laden, the US special forces found Yarosh's business card." Adding to the sense of farce, US news network CNN called the number on the card only to reach a baffled-sounding woman who said she had nothing to do with Pravy Sektor. Contacted by AFP, Pravy Sektor described the whole episode as "propaganda worse than that of Nazi Germany". "As if the militants of Pravy Sektor carry Yarosh's business cards with them!" said the group's spokesman Artem Skoropadski. Pravy Sektor was at the forefront of the street protests that forced the February ouster of Ukraine's pro-Kremlin president Viktor Yanukovych. Its nationalistic outlook is viewed with great disquiet, verging on disgust, by a large part of the Russian-speaking population in eastern Ukraine. Separatists, supported by the pro-Kremlin Russian media, have used the presence of the group to justify their rejection of the new authorities in Kiev. They are included in the list of groups that must disarm under the agreement signed between Russia, Ukraine and the West in Geneva on Thursday.