The behavior you are describing would be considered a form of harassment and griefing (with regard to the building system) and as such, violates the rules of behavior.
- Abuse of the claim system (claim spam) where blocks are placed for no other purpose than to prevent other player’s access to resources and building spots.
I would recommend reporting this clan with your proof to @Ignasi and/or @Hugo in accordance with Funcom’s rules: https://forums.funcom.com/t/please-read-official-servers-terms-of-conduct-guidelines-and-procedures/112678