Prison director Brian Edwards said a number of housing units at the medium-high-security prison were still out of action in the wake of the April 6 incident.

Furniture was destroyed, glass broken and water damage sustained, Mr Edwards said.

‘‘The incident did not include any loss of the security integrity of the establishment or security of the wings,’’ he said.

But the incident was serious enough to spark a lockdown and prisoner relocation.

Mr Edwards attributed the problem in large part to an influx of remand inmates. He said up to 30per cent among those on remand had extreme drug dependence.

‘‘Within those particular areas, with mainly remand prisoners from different areas in Tasmania, we think when they were remanded they were on the list of being extremely dependent on drugs,’’ he said.

Police from Bellerive CIB are  investigating the incident and calculating damages .

Mr Edwards said those involved would be pursued to recoup costs.

He insisted there was nothing to suggest the incident was related to a smoking ban introduced earlier this year.

‘‘But it did involve a connection with illicit drugs and the current difficulties we face with various factions all being held within one prison,’’ he said.

He said there were ongoing issues managing the state’s prison population, despite inmate numbers remaining well below capacity.

‘‘In some units we’re always struggling with some of our building classifications due to gang difficulties, feuds, crimes, protection issues and area loyalties,’’ he said.

He said units damaged in this incident had since been cleaned by staff and prisoners.