Two Arsenal players were involved in a heated row on the team bus after their Champions League draw with Rosenborg on Wednesday evening.
Norwegian police were called upon to separate two players reported to be captain Patrick Vieira and right-back Lauren.
Trondheim police officer Erik Svensson said: “Two police officers had to go on the bus and then it was calmed down.”
The row is thought to have arisen over the defending when Rosenborg scored.
It has also been reported that fellow Arsenal players stepped in to pull the players apart.
Rosenborg’s head of security Hallgeir Stokken added: “There was an argument between two players which turned into a physical confrontation.
“I have been told that other Arsenal players had to step in to separate them.”
Arsenal refused to comment on the incident.