Alleged South Australian killer Robin Michael, accused of murdering his wife Kerry on Mount Roland in February while on holiday, was found dead in Risdon Prison on Monday.

It follows the death of prisoner Troy Colin Monsoon, 42, of Wynyard in the back of a prison transport van that travelled between Launceston and Hobart on June 22.

Prisoners Advisory Legal Service spokesman Greg Barns said two deaths in custody in a week was ‘‘unconscionable’’.

‘‘There is a serious systemic problem in Tasmania Prison Service with adequate resources in mental health services,’’ he said.

‘‘What has gone wrong in Tasmania that we have two deaths in a week?’’

It had been reported that Mr Michael, 63, had self-harmed just before being arrested in Devonport for the alleged murder of his wife.

Questions to the state government about whether Mr Michael was on suicide watch at the time of his death were not answered on Monday.

Attorney-General Vanessa Goodwin released a statement on Monday afternoon announcing an internal prison inquiry.

‘‘I am deeply concerned that another death custody has occurred so soon after last week’s tragic incident,’’ she said.

‘‘Consequently, I have requested urgent advice from the Tasmania Prison Service on what immediate actions are being taken in response to this latest incident.’’

Tasmania Police were notified of the death about 8am and will prepare a report for the coroner.

Bellerive Inspector Doug Rossiter said other inmates in the vicinity when the death occurred were being interviewed but police didn’t suspect anyone else contributed to Mr Michael’s death.

Ms Goodwin said she would carefully consider any recommendations stemming from the internal investigation and the coroner.

Mr Barns said there had already been a host of inquiries into deaths in custody and they shouldn’t still happen in 2015.

‘‘In every case coroners have said prisons have to be vigilant when it comes to the health of inmates,’’ he said.

‘‘I’d urge the government to release as much information as possible because the deaths have occurred on their watch.’’

A coronial inquest into five deaths in custody was conducted in 2001.

Then coroner Shan Tennent made 29 recommendations ranging from the removal of hanging points within prisons to a better system for communication between inmates’ families and prison authorities.

Mr Michael, a former health administrator, had pleaded not guilty to killing his wife near the summit of Mount Roland.

It was reported that after allegedly killing his wife Mr Michael wrote on Facebook that she’d admitted being in a relationship with a mutual friend.

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