The Korea Football Association (KFA) are investigating the incident and will convene on Friday to discuss disciplinary action against the four players.
"Under KFA regulations, they may be suspended for more than six months," a spokesman told AFP.
He added: "They have fully admitted their misbehaviour, saying they would humbly accept any disciplinary measures."
Veteran Lee Woon-Jae, who is on the shortlist for the Asian Player of Year award, issued a tearful apology at a press conference at the KFA's headquarters.
"I am so sorry," he said. "As captain, it is my responsibility, the other players did nothing wrong. I will accept any punishment that comes my way."
