The Broncos are investigating and the NRL Integrity Unit has also been informed.
Reynolds and Carrigan can be seen in the video, which appeared on social media platform X, having a wrestle after on Sunday following the club's fan day.
A female witness to the scene can be heard calling out, "Adam ... Pat ...stop."
Brisbane are aware of the altercation and released a statement.
"The Broncos are looking into an incident involving some of its playing group in Brisbane City last night," it read.
"The club was made aware of the incident last night and has been speaking to players across the course of the day to clarify details of what occurred.
"The NRL Integrity Unit has been informed of the matter."
Best fans in the comp 🫶— Brisbane Broncos (@brisbanebroncos) Thank you to each and every one of you who came and showed love at our 2024 Fan Fest � pic.twitter.com/y7aUsxTgiUFebruary 11, 2024
Both Reynolds and Carrigan are senior leaders at the club and two of the vital cogs in the Broncos' quest to go one better than last year, when they suffered grand final heartbreak in a 26-24 loss to Penrith.
Sunday was a massive day on the club's calender with thousands turning out to meet the entire squad, including Reynolds and Carrigan.
Players then went out afterwards for a social gathering.
RL Broncos
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