Greece and Turkey fought a brief dogfight on Twitter over Turkey's downing of a Russian warplane due to an error by an aide in Greek Prime Minister Alexis Tsipras' office, a Greek official said on Monday. It began in the middle of a summit between Turkey and the European Union on Sunday, when a message appeared on Tsipras' Twitter account saying: "To Prime Minister Davutoglu: Fortunately our pilots are not as mercurial as yours against the Russians." A second tweet issued in Tsipras' name referred to near-miss aerial incidents between Greek and Turkish planes over the Aegean Sea, saying: "What is happening in the Aegean is outrageous and unbelievable".