Same happened to me also, It was really strange, site was working normally in desktop browser, but if it was accessed from mobile a lot of pop-ups was displayed. In my jetpack status still the following links are appearing as outgoing traffic, can anybody suggest me a fix.
my site https://welcometonature.org
Outgoing Clicks
acdcadz.com/Doo/PPppup.php
ecs1.engageya.com/gas-api/click.json?xxxxxxxxxxxx…
acads.net/Do/PPup.php
53.campaignism.com/WhiteLabelBidRequestHandlerServlet?xxxxxxxxxxx