12/08/2014 08:01 EST | Updated 02/07/2015 05:59 EST

Palais des congrès defaced by anti-Plan Nord graffiti

Workers at Montreal's Palais des congrès are cleaning paint off the windows of the convention centre after the building was defaced by anti-Plan Nord slogans.

Paint was splashed and anti-Plan Nord posters were pasted to the windows of the Montreal convention centre overnight ahead of the Board of Trade's Strategic Forum on Natural Resources.

"Non Plan Mort" — or "No to Plan Death" — was also sprayed on the windows.

Plan Nord is the provincial government's plan to develop natural resources in Quebec's north.

A demonstration was set to take place before the 7:30 a.m. convening of the forum on natural resources.

Of the dozen or so protesters, three have been detained by police for disturbing the peace.