Celtic have released a statement condemning fans that demanded Neil Lennon's departure from the club outside the club's stadium.
Supporters descended on Parkhead around full-time as the club fell to another defeat against Ross County, exiting the Betfred Cup in the process.
Hundreds were at the gates by the time police arrived on the scene and Celtic have slammed the behaviour as they insisted some players were left "shaken" by the angst.
They insist club personnel were targeted with missiles and have promised a full investigation.
The statement read: "Everyone at the club is hugely disappointed by this afternoon’s result, one which has ended our phenomenal run of 35 consecutive cup victories.
"While we sincerely share the huge disappointment of all Celtic supporters, there can be no excuse for some of the violent scenes at Celtic Park this evening. The club will be investigating these events fully.
"For players and a management team, who have given so much in recent years and have delivered 11 consecutive trophies, to require an escort from Celtic Park while being targeted with missiles, is simply unacceptable.
"While we understand that only a small number of people were involved in this behaviour, some of the actions this evening, which have obviously left our own players shaken, cannot be condoned in any way."