A video of the two grabbing each other aggressively circulated across social media on Monday.
One person can be heard repeatedly saying, “Reyno” while another says, “Adam, Pat, stop”.
It is understood that the pair, alongside several other Broncos players, spilled out of a pub having earlier participated in the club’s fan festival at Red Hill on Sunday.
No punches were thrown but CCTV footage captured multiple people wrestling before the scuffle between Reynolds and Carrigan.
The Broncos have since released a statement, confirming the NRL Integrity Unit has been informed of the matter.
“The Broncos are looking into an incident involving some of its playing group in Brisbane city last night,” a club statement 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 Broncos are set to travel to the US in 10 days to prepare for their historic premiership launch in Las Vegas on Sunday, March 3.