"Officers attached to Mid North Coast Police District are investigating reports of an alleged assault which occurred at a nightclub on William Street, Port Macquarie, about 3am yesterday (Sunday 2 October 2022).
"Police have been told a 16-year-old boy was punched by a man.
"Inquiries are continuing and anyone with information is urged to contact Crime Stoppers on 1800 333 000."
Seven reports the alleged victim suffered serious injuries and is helping police with the investigation.
Curran last week featured in the Prime Minister XIII's annual clash against Papua New Guinea.
The match was held at Suncorp Stadium with the Australian team captained by Daly Cherry-Evans winning 64-14.
The New Zealand Warriors acknowledged the investigation into Curran but didn't reveal further details of the incident.
"The club wishes to advise that the incident has been reported to the NRL Integrity Unit and will now await any further information from the NRL investigation," Warriors CEO Cameron George said in a statement on Tuesday.
"The club will make no further comment on this matter."