Canterbury winger Addo-Carr, a Gunggandji, Birrbay and Wiradjuri man, was one of several NRL players who travelled to Tuggerah for the 51st edition of the renowned Indigenous football tournament.
On Saturday afternoon, a fight broke out during a match between Addo-Carr's Sydney All Blacks and Walgett Aboriginal Connection.
Footage of the incident appears to show the State of Origin and Australian representative brawling with a rival player.
NSW Police said on Sunday that officers from Tuggerah Lakes Police District were "working closely" with event organisers and the National Rugby League, which is looking into the incident.
At about 1.45pm on Saturday, two teams were taking part in the rugby league carnival at the Central Coast Regional Sporting Complex "when an on-field fight broke out", police said in a statement.
"Some players and spectators attempted to break up the fight, which then spread off-field, whilst others became involved.
"Police and event security broke up the brawl a short time later and the crowd dispersed before the game was called off."
There have been no reports of injuries.
Bulldogs general manager of football Phil Gould took to Twitter to address the incident in a since-deleted tweet, confirming the club had been in contact with Addo-Carr.
"Bulldogs have spoken personally to Josh Addo-Carr and he is fine," Gould said.
"No issues at all. Unfortunate incident, but he's taken no harm. More as it comes to hand."
Bulldogs management has been contacted by AAP for comment.
7°C