Barnsley has registered a complaint to the Football Association and the English Football League over an alleged incident involving their manager Daniel Stendel and Fleetwood boss Joey Barton.
Barnsley player Cauley Woodrow wrote on Twitter following Saturday’s match at Oakwell, claiming that Barton, 36, "physically assaulted" Stendel in the tunnel after the final whistle.
Woodrow later deleted the tweet.
On Monday, South Yorkshire Police said they were continuing to investigate reports of an assault at Barnsley Football Club.
"No arrests have been made at this time and enquiries remain ongoing," a statement added.
Fleetwood said they had "been made aware of an alleged incident" and were "currently establishing the facts".