About 20 demonstrators, who had gathered outside Denmark's Environment Department, forced their way into the department Grøn trepart in central Copenhagen on Wednesday, but later left the building after a police request.
Duty officer Henrik Svejstrup said that 22 demonstrators were inside the building on Wednesday afternoon, but that all had left the premises after the request.
The demonstrators are now being accused of disturbing the peace.
About 30 demonstrators from, among others, Green Youth were outside the department during the protest.
The department Grøn trepart focuses on the transformation of, among other things, Danish agriculture.