Where did those pageviews come from?

I suddenly got hundreds of hits on a recent post which was latest post before the previous post and this post being published. It's been going on for about 7 hours, I only noticed after published previous post.

Those requests came from US and no any related entries in Source tab (not referrer or search engine),

Those pageviews from US

I also checked Google Analytics, but no such sudden views.

I am thinking, someone must be trying something. If it's an attack why that post?

Then, I thought it could be scarper, but very bad one. Not the intention but the skill of coding and probably didn't notice it's been grabbing same page again and again.

I hope this will stop soon.