Rakhat Aliyev was found dead in a Vienna prison earlier this week. Photo: Reuters

Sedatives were found in the body of Rakhat Aliyev, the Kazakh dissident who was found hanged in an Austrian prison earlier this week after he left Malta claiming he was being persecuted by his country’s regime.

Mr Aliyev was being held in solitary confinement but was found hanged in a bathroom in what was later revealed as “a very long and painful death”.

He was the former son-in-law of Kazakh President Nursultan Nazarbayev until he fell out with the regime and sought refuge in Malta for a number of years.

He left soon after a rare interview with The Sunday Times of Malta in July 2013, in which he said his country’s secret service had established a network with a mission to “kidnap or kill” him.

Only two hours after his body was found, corrections department director Peter Prechtl made an announcement concluding Mr Aliyev committed suicide. The fact that no investigation or autopsy had yet been done is one of the reasons Mr Aliyev’s Austrian lawyer, Klaus Ainedter, is convinced of foul play.

“It’s now off the table that he committed suicide,” Dr Ainedter said. In comments to this newspaper last week, he said he was the last person to have met Mr Aliyev and there were no thoughts of suicide.

Dr Ainedter told The Sunday Times of Malta yesterday he had requested the intervention of the FBI in investigations surrounding Mr Aliyev’s death. Apart from the hasty determination of the cause of his death, he pointed out Mr Aliyev was due to testify against two fellow prisoners demanding money from him not to kill him. The court case was scheduled for the day he died, after Mr Aliyev refused to pay the money.

It’s now off the table that he committed suicide

Mr Aliyev’s trouble with the regime started in May 2007 after he strongly objected to his then father-in-law’s decision to amend the constitution to become president for life.

He was sentenced in absentia to 40 years’ imprisonment for a number of crimes, including the kidnap and torture of two bankers.

A former Kazakh ambassador to Austria, Mr Aliyev became a vocal critic of his country’s President and had denounced the case against him as politically motivated.

His trial for the murders was scheduled to be held around Easter in Austria, after Vienna twice refused to extradite him to Kazakhstan because of the country’s human rights record.

Dr Ainedter suspects Austria did not manage to protect his right to a fair trial. Another reason why he is convinced this was not suicide relates to the fact that the doctor appointed to conduct the autopsy was listed as a witness for the prosecution in the murder trial.

Lawyers are requesting a second post-mortem and calling for an investigation by forensic and medical experts to establish the truth surrounding Mr Aliyev’s death. They will be addressing a press conference in Vienna tomorrow.

Meanwhile, Kazakh President Nazarbayev called a snap election the day after his former son-in-law was found dead.