A doctor imprisoned in the United Arab Emirates on a manslaughter charge has spoken of his joy and relief at being home.

Professor Cyril Karabus, a 78-year-old paediatric oncologist from Cape Town, said it was “fantastic” to be free after a nine-month ordeal in which he had witnessed the effects of beatings and despaired of ever being released.

He was arrested at Dubai Airport in August as he attempted to transfer from a flight from Toronto where he had been celebrating his son’s wedding.

He didn’t know he had been convicted in absentia for the manslaughter of a terminally ill three-year-old Yemini girl he had treated for leukaemia at the Sheikh Khalifa Medical Centre in Abu Dhabi more than a decade earlier.

“As soon as I landed in Dubai they took me away and shouted ‘you’re a murderer’,” he said at his home in Kenilworth. “My passport was taken. I didn’t know what was going on.”

He spent the night at the airport’s prison before being transferred to two others. “It was an empty room with just a metal bench to sleep on. At the Al Wathbah prison we were four men in a cell. Two were 25-year-old boys who were accused of murder. They were Emirates students and one of them had studied at Cambridge.

“They had been beaten by a drunken policeman they got into a fight with. One was hit so badly that he was paralysed down the right side of his body. He had to learn to write with his left hand.”

Prof Karabus was cleared in March after 17 court hearings. He said: “It was a complete shambles. The people they said had given evidence against me never appeared in court. At times I didn’t know what was going on – sometimes they had no translator and sometimes they would only translate one or two sentences. When the judge said I was free to go, I just cheered.”

He said he had been surprised by the number of well-wishers who had greeted him on his return. “It was amazing. I expected some, but not that many.”

Now he just wants to get to know his three-month-old grandson, Gabriel, who was born while he was in prison.