Against Unauthorised Construction

I had given a complaint against unauthorised construction to mcd .on my complaint mcd sealed third floor .but builder broke the seal and built flats on third floor .I again gave complaint the mcd resealed the third floor .and request to police to provide force to demolish the third floor .but police is with builder they are not giving force .the builder again broke the seal and get entered the people in the flats. what should I do ? should I go to court or other agency ? mcd is saying that mcd has registered FIR against them.