downvoting harrassment

Dear staff, 

I recently found some malicious attempts toward my reviews that on one day someone intentionally downvoted all my reviews one by one, its a highly abnoxious internet meme that i never expected could happen at IMDb site which is strictly observed by staff members, wouldn't be better it can be improved in terms of making downvoting totally restricted like many other sites, just a point of view from a contributor, thank you.