A Just Stop Oil supporter has used a fire extinguisher to spray paint on a University of Exeter building.
The campaign group said the protest aimed to "make a public statement calling on the government to end new oil and gas projects".
The group said the supporter used buckets of paint and spray cans to daub the glass facade of The Forum, on Exeter University's Streatham Campus, with paint.
They said the protest happened at about midday on Tuesday 10 October.
Responding to the incident, the university said it "respects the right to protest providing it is carried out safely, respectfully and within the law".
Just Stop Oil said the supporter, named George Simonson, then climbed on top of the lobby entrance and remained there while police and campus security tried to bring him down.
Mr Simonson, a 23-year-old mechanical engineering graduate from London, said he wanted to "put shockwaves through the system".
The university said in a statement: "The protest being held at the University's Streatham Campus has concluded peacefully.
"The University respects the right to protest, providing it is carried out safely, respectfully and within the law."
On Monday 9 October, paint was also thrown in an incident at the University of Bristol's Queen's Building.
Ben Meehan, a student at the University of West England, has been charged with criminal damage and has been released on bail.
The 21-year-old is due to appear at Bristol Magistrates' Court on 5 December.