My ad blocker settings in safari usually stops most of this but I’ve just had a load more pop ups and this time on my phone, including ones saying I have won a prize and one where they have detected a virus and recommending that I purchase software to remove it/an ad blocker to stop it happening again.
Obviously I won’t take them up on their kind offer, but something very odd has happened...
Looks like it might be Google ads to me (see that sideways triangle with the ! in it - this is on shown Google Ads).
Perhaps in AdSense the site settings to allow Google to place ads automatically has been activated. I have this on one of my low-volume websites to see how it works and it's awful in that it messes up the page layout, although it does not pop-up that I've seen.
I normally use Ad Block Pro and have not seen the pop-ups on this site (Chrome on MBP). I also use Opera to read news sites as it manages to calm down the Daily Mail* adverts, if not the content!