evidence: Imran Khan, Pakistan's hugely popular former prime minister, was arrested on Tuesday on corruption charges - a moment he had successfully avoided for several months. [...] Leaders and supporters of Mr Khan's Pakistan Tehreek-e-Insaf (PTI) party argue this is proof of the army's involvement. They say the arrest has little to do with corruption charges and everything to do with Mr Khan's ongoing public battle with the army. He has accused the army and the spy agency, the Inter-Service Intelligence (ISI), of conspiring to assassinate him - he survived a shooting last year. [...] Analysts believe that Mr Khan's arrest only adds to the growing instability and diminishes any chance of a resolution between the former PM and the establishment, be it the government or the army.