Youth pranksters lobbed eggs and apples at cars off the Library Bridge earlier this month.
Police were called to the campus on November 4 after receiving reports that a “large number of youths were heading towards Alcuin College throwing eggs and apples at cars and houses.”
The group were then spotted in the area of Derwent College and the library at 6.50pm.
An eyewitness at the scene said that police had ejected people from the library café and were “hiding inside” in the hope of catching the would-be offenders out, but a police spokesperson later said that this was not the case.
However, when the police attended, the youths were not there.
This incident was the latest in a string of similar anti-social behaviours spanning previous consecutive nights, originally starting as a Halloween prank, according to a member of the library staff.
It is not known whether the miscreants were university students or not and no arrests have been made.
A university spokesperson said: “This sort of behaviour is completely unacceptable on campus and the University is working closely with North Yorkshire Police to ensure there is no repetition.”
A North Yorkshire Police spokesperson added that they had received a call of reports of a large number of youths “throwing eggs at cars and houses”.