The political leadership initially consisted of Denis Pushilin, self-appointed as chairman of the government, while Igor Kakidzyanov was named as the commander of the "People's Army". Vyacheslav Ponomarev became known as the self-proclaimed mayor of the city of Sloviansk. Ukrainian-born pro-Russian activist Pavel Gubarev, an Anti-Maidan activist, a former member of the neo-Nazi Russian National Unity paramilitary group in 1999–2001 and former member of the left-wing populist Progressive Socialist Party of Ukraine, proclaimed himself the "People's Governor" of the Donetsk Region. He was arrested on charges of separatism and illegal seizure of power but released in a hostage swap. Alexander Borodai, a Russian citizen claiming to be involved in the Russian annexation of Crimea, was appointed as Prime Minister, while Igor Girkin was made defence Minister. On 6 April, the group's leaders announced that a referendum, on whether Donetsk Oblast should "join the Russian Federation", would take place "no later than May 11th, 2014." Additionally, the group's leaders appealed to Russian President Vladimir Putin to send Russian peacekeeping forces to the region.