Detective Inspector Mike Arnerich said the police were treating the incident as a homicide and still in the early stages of their investigation.
"Until the results of the post-mortem are complete and a likely cause of death is established, the man's death is being treated as suspicious.''
There are about 30 officers working on the case today, including scouring side streets where a pile of loose change has been found.
The missing cash box is described as being 26 centimetres in length, about 11 centimetres in height and12 centimetres in depth.
Mr Curry has been remembered by one colleague and friend, Violet Campbell, as a lovely man.
"He's good at giving people advice, he helps me out.
"He can never say anything bad about anybody.''
Mr Curry was looking forward to a trip back to his homeland Samoa next month, she said.
"He was so excited for that.''
The police have set up a dedicated 0800 free phone number for anyone who has any information on the whereabouts of Mr Curry's cash box or anyone who was in the vicinity of the Waterloo Interchange bus depot last night, between 6pm and midnight who may have witnessed anyone or anything suspicious.
Detective Inspector Thomson says commuters would have been returning to Lower Hutt by train and bus last night and may hold vital information for Police.
Anyone with any information in relation to the investigation should contact the 0800 free phone number: 0800 OP WATER (0800 679 2837).