Physicist Dmitry Kolker – a laser expert – was suffering from advanced pancreatic cancer and was taken from his hospital bed to Siberia, where he was being fed through a tube. He was taken on a more than four-hour flight to Moscow, where lawyers said he was taken to Lefortovo prison before later dying in a nearby hospital. The 54-year-old had been accused of betraying state secrets to China. His cousin Anton Dianov said the accusations against the scientist were “absolutely ridiculous”. He said: “He was a scientist, he loved his country, he worked in his country despite many invitations from leading universities and laboratories to go and work abroad. “He wanted to work in Russia, he wanted to teach students there. “These charges are absolutely ridiculous and extremely cruel and unusual to impose on such a sick man. “They knew he was on his deathbed and they chose to arrest him.” “Treason charges were based on lectures” Family and lawyers said Kolker was arrested and his home was searched by the FSB security service. They said the treason charges – which carry up to 20 years in prison – were based on lectures he had given in China, even though the content had been approved by the FSB. Lawyer Alexander Fedulov said he had tried to contact the authorities on Mr Kolker’s behalf but had been removed from the FSB’s investigative department and from prison. Read more: Latest Ukraine – Russia ‘almost certain’ to turn to seize Donetsk He said he would file a legal complaint about the scientist’s detention conditions. Several Russian scientists have been arrested and charged with treason in recent years for allegedly leaking sensitive material to foreigners. Kremlin critics say the arrests often stem from unfounded paranoia.