A Russian couple went on trial Tuesday accused of the gruesome killing of their 26-year-old daughter, allegedly beating, disembowelling and trampling her to death in an attempted exorcism on Christmas eve. Investigators said Sergei Koshimbetov, a 49-year-old taxi driver, and 50-year-old Elena Antonova, a teacher, of the central Russian city of Voronezh, tortured their daughter for several hours before killing her on the night of January 7 when Orthodox Russia celebrates Christmas. On the pretext of \"exorcising demons\" they first beat up their daughter and tried to force-feed her five litres (11 pints) of what they claimed was \"holy water.\" \"After that, Antonova ripped a part of her daughter\'s intestine out with her hands,\" investigators from the Voronezh region said in a statement. \"After that the husband and wife trampled her body until she died.\" The parents, who deny the killing, were ordered to stand trial despite being deemed mentally ill by psychiatrists, the investigators said. They were expected to be committed to a mental institution. \"I absolutely did not kill her,\" Antonova said on television. \"What I did, I did to her body.\" Investigators said the couple insisted they wanted to save her from evil. \"The mother and father believed they were helping their daughter to stop loving her husband, believing him to be Satan,\" investigator Murat Suroyev said in televised remarks. When their daughter Alexander stopped breathing, her parents wrapped her in a blanket telling relatives she would be resurrected in three days, state-controlled NTV channel said. The next day their younger daughter called an ambulance. Medics said they were shocked by the scene. \"The woman was lying in some kind of a crucifix position,\" paramedic Irina Semirod said. Citing the findings from the Serbsky psychiatric hospital, investigators said the parents were mentally ill and needed to undergo treatment. Arriving at the hearing with a Bible, Antonova said she did not understand why she had to be committed. \"How can they send me to a madhouse?\" she said. \"I feel fine.\"