Football bosses last night launched an urgent probe after two of Northern Ireland's biggest stars swapped blows as they boarded a flight from Iceland.
Stunned Northern Ireland fans and other passengers looked on in amazement as Keith Gillespie and George McCartney's sensational bust up kicked off as the two players got on the scheduled flight from Reykjavik to London yesterday morning.
Players, fans and members of the press had caught the flight following Northern Ireland's disastrous 2-1 defeat to Iceland in Wednesday's must-win European qualifier clash.
The astonishing altercation only ended when team-mates David Healy, Warren Feeney and Steve Davis jumped in to separate the feuding pair.
Onlookers say goal ace Healy received several punches as he tried to pull the sparring team mates apart.
And although team manager Nigel Worthington was on the plane, it is believed he missed the incident although the flight crew informed him immediately afterwards.
It is understood the two seniro players fell out over a missing passport.
Irish FA Chief Howard Wells confirmed that the governing body had already launched a probe into the amazing flare-up.
The football boss says the incident brought a disappointing close to a nine-day international trip that saw Northern Ireland crash to Latvia and Iceland, destroying their chances of qualifying for the European championships.
Sheffield Wednesday winger Gillespie was already smarting from scoring the own goal that sent his team spinning to a 2-1 defeat and out of any realistic contention for a place in the Euro 2008 finals.
Mr Wells said: "I will be the first to admit this isn't helpful.
"It doesn't help the image of the IFA and it doesn't help the image of the game, but we are where we are and we have to deal with it.
He added: "There was an altercation and I understand blows may have been thrown.
"I am annoyed. It has been a very difficult trip for the nine days. We will deal with this, it's not something we will duck.
"We will assess what happened and why and take whatever action is appropriate. It will be resolved quickly, as we can't let this fester."
Mr Wells described the mood within the Northern Ireland camp as " excellent" despite the back-to-back defeats and yesterday's fall out.
Witnesses say words were exchanged between the two players before punches were landed as tempers flared.
Sky Sports reporter Pete Colley, who witnesed the punch-up, said: " Keith (Gillespie) was talking to George (McCartney) who was putting his stuff in his lockers above the seats. V
"Voices were raised and Keith appeared to push him, which led to fists.
"I have to say that George McCartney defended himself. David Healy was the first person on the scene.
"He got into the middle and received a couple of punches himself for his troubles."
In a statement the IFA said both Mr Wells and the association's president, Raymond Kennedy, will investigate the outbreak of violence between the two players.
West Ham defender McCartney only recently returned to the Northern Ireland set up after a fall out with former Northern Ireland manager Lawrie Sanchez.