Labour Party members attending a closed meeting were targeted by pro-hunt demonstrators who stormed the building.
About 100 campaigners gathered at the venue in Kidderminster, Worcestershire, to protest against hunting legislation.
West Mercia Police said a smaller number managed to force their way into the building in Hoo Road and stop the meeting on Thursday night.
A force spokesman said doors and windows were damaged but no-one was injured during the incident.
The protesters were ejected and, following a peaceful protest, they dispersed.
The party members, who were interrupted about half-an-hour into a meeting which started at 1930 BST, left a short time later.
It was the latest in a string of public protests against legislation to ban hunting with hounds.
There were angry scenes in Stoneleigh, Warwickshire, on Thursday when demonstrators surrounded Agriculture Minister Lord Whitty after he made a speech to dairy farmers.