PHNOM PENH, Cambodia (AP) — The former head of state of Cambodia’s 1970s Khmer Rouge regime has rejected the charges of genocide and other crimes against him, saying they were concocted by the country’s traditional enemy, neighboring Vietnam.

The 85-year-old Khieu Samphan delivered closing remarks Friday at his U.N.-assisted trial. He denied knowing about crimes including forced marriage and the fate of minorities while the Khmer Rouge held power, saying he only discovered them after the regime’s fall in 1979.

His 90-year-old co-defendant Nuon Chea did not appear in court, but through his lawyer called the tribunal a show trial.

The two men already received life sentences in 2014 for crimes against humanity. Some 1.7 million people are estimated to have died as a result of the communist group’s extremist policies.