A US court has blocked the deportation of John Demjanjuk, the Nazi war crimes suspect who was due to fly to Germany on Sunday.The judge said that in the four years since the deportation was ordered his health has seriously deteriorated. The 89-year-old is suffering from pre-leukemia, kidney problems and spinal pain. Germany has accused Demjanjuk-a Ukrainian-of being an accessory to 29,000 murder counts while a guard at the Sobibor death camp in Poland. Demjanjuk has been contesting Nazi war crimes charges for over 20 years. He was extradited from the US to Israel, where he was convicted in 1986 of being “Ivan the Terrible” a prison guard at the infamous Treblinka concentration camp. His conviction was later overturned by an Israeli court on appeal.