"The victim is recovering with support, but is shaken and has not been able
to return to work since the incident," Underhill said.
Police have been following "strong lines" of inquiry but are asking for the help of the public.
Underhill said police knew people filmed the event and were asking for them to come forward with their footage.
"There were people present on the night who recorded the incident – I'm interested in any footage that people have depicting the assault or the offender."
If you were present or have any information that might be useful to the investigation and identifying the offender Hutt Valley Police ask you come forward or call 04 560 2600.