I just noticed that one particular site has almost 7000 backlinks linking back to our website. The site is something like a news aggregator and for each post they created around 20 (sometimes much more) backlinks back to our page and they basically linked over 400 pages.

I am beginning to get concerned that this amount of links might harm our page. They seem to have more backlinks to our page than all the other pages combined and more backlinks that our website has pages.

We have seen a massive negative effect going on for quite a while and the PageRank seems to have dropped to None (Not even 0). But I am not sure when and why exactly that happened seeing that PageRank updates take quite a while to appear. The site linking to us is otherwise pretty reputable and doesn't seem to be having any problems with their rank. (PR 6 actually)

I was thinking of using the Google disavow tool for this site, but I don't want to make things even worse. Do you think these are harmful? If so, how do I fix this? Thanks :)