A mentally disabled British man, held in a Spanish jail for 17 months without trial, has become suicidal and should be released, his elderly mother said yesterday.

Andrew Dmytruk, 51, who was brain damaged after contracting meningitis as a baby, has been on remand since being accused of arson when a fire broke out in his Benidorm hotel in December 2010. His widowed mother, Doris O'Brien, who insists he is innocent, said he recently became so desperate that he slashed his wrists and throat.

"He couldn't stand it any more. This chap found him lying in his own blood, convulsing. He so nearly died," said Mrs O'Brien, 77. "It is disgusting. He was 13 stone when he went into prison. Now he is about eight stone, his bones are sticking out and he has lost teeth. He can't eat the food so he is refusing it.

"He is like a 10-year-old, quite jovial but when he gets mad he has childish tantrums. He can't understand why he is in jail and nor can I. He has never harmed anybody, never been in trouble with anybody," said the retired factory supervisor from Nottinghamshire, who has been borrowing money from family to fly to Spain monthly.

Mr Dmytruk's case has now been taken up by the charity Fair Trials International, which is calling for him to be either tried swiftly or released on bail. Its chief executive, Jago Russell, said yesterday: "Andrew has been held in prison for nearly 18 months with no trial date in sight. We are very concerned for his well-being so far away from home, in a world he struggles to understand, and hope the Spanish authorities deal with the case as quickly as possible and reconsider the decision to keep him in prison."

Mr Dmytruk was holidaying with his mother when a fire broke out in the early hours of the morning in a fourth floor room of the Ambassador Playa Hotel. The guests, who were mostly British, had to be evacuated and several were treated for smoke inhalation.

Despite his mother's assertions that he was asleep in their room on the second floor at the time, the hotel claimed he had been spotted on CCTV near the site of the fire. Mrs O'Brien said her son was terrified when he was arrested and taken away by Spanish police: "He just screamed, 'Mum what are they taking me for? What have I done?' It was terrible. I was in that much shock that I didn't know what to do."

Mrs O'Brien, who has been Mr Dmytruk's sole carer for many years, said that on 21 December 2010, he returned from a night out with friends and mistakenly got out of the lift on the 4th floor but was "fast asleep" in his room when the alarm was raised.