Officers on the scene at 12th and Nanaimo streets blocked off streets and interviewed people in the area as they searched for clues Tuesday night.
The Last Door Recovery Centre has identified the worker as 39-year-old Jason Collett. It says Collett had been at the recovery home since April 2012.
Collett worked as crane operator by day and as an evening support worker at Last Door's adult program according to the centre. He was also a certified search and rescue volunteer.
On its Facebook page, the recovery centre expresses "extreme sorrow" at his death.
"Whether Jason was waving at you from a crane tower over Metrotown, pruning a tree, or working through some written exercises with a client, he was kind, courteous, considerate and diligent."
Last Door Recovery says it operates the Nanaimo Street facility as a transitional living residence for clients who have completed five months of primary care treatment.
It has been operating in New Westminster for the last 30 years and says it has never before experienced this kind of incident.
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