Two RAF Typhoon pilots due to fly missions over Libya were sent back to the UK for "inappropriate behaviour", it has emerged.
The men, based at Gioia del Colle in Italy, returned to RAF Coningsby in Lincolnshire at the end of March.
The disciplinary action followed a night's drinking, but the MoD was unable to confirm whether the pilots were declared unfit to fly.
A spokesperson said two personnel had been "returned from detachment".
The incident at the Gioia del Colle base, where the RAF's Typhoon and Tornado fighter jets are based, is understood to have led to a temporary alcohol ban for other RAF personnel serving in the Mediterranean.
In a statement, the MoD said: "Two RAF personnel have been returned from detachment in Gioia del Colle following inappropriate behaviour; this has not affected the RAF's ability to sustain its current commitments.
"Individuals who are found to have fallen below the high standards of conduct demanded by the RAF can face appropriate internal action."
Gerry Connelly, a retired Air Vice Marshal and former commander at RAF Wittering in Cambridgeshire, described the news as "disappointing".
The ex-fighter pilot said: "What's gone on, we don't know - but what I do know for certain is that the RAF takes a very firm view of any activities like drinking in and around flying, particularly in these sorts of conditions because clearly the two don't mix.
"There are very strict rules and they're very strictly enforced and if people step over the line they will be dealt with pretty harshly.
"You could argue that being sent home from Gioia del Colle is not very harsh in some ways but it would be for them a big issue, and they will have to face the consequences of whatever their actions are."
The southern Italian airfield is the forward operating base for the RAF during the Libya campaign.
Twelve of the UK's Tornado jets and six Typhoon fighters - used to carry out bombing missions and patrol the no-fly zone - are stationed there.
The aircrafts' pilots have so far flown more than 70 sorties, according to the MoD.