Unwanted content found via webpagetest

Hi guys I've encountered some unwanted code while doing some performance testing with Webpagetest. It consists of advertisement and pictures from Spywebshop(?) about 20 lines at the end of the rendering of the website. At first I thought it was part of the adsense I'm running but it's not.

Can someone give me a few ideas on how to remove this from my website as it ads a few seconds(!) to the loading time.

Thanks,
Nick