It's obvious when it's searched for using the title of the article "Mass shootings surge" at a news aggregate.

Anyone looking at their local online news would only see the article for their area.

I went and did the search myself, took some screenshots and put together a writeup to share out on social media. The articles themselves follow a template, and are of course all written by the same author(s). Here's the write up I included with my screenshots.

This is what a coordinated anti-gun campaign looks like.

(These are MY screenshots. No some fabrication I found on the internet.)

The first three paragraphs are cut from a template with different numbers and names filled in, the rest of the article is nearly identical as well.
All written by the same two "reporters" and distributed out to online news affiliates across the country.

Don't believe me? Good. Go search it read the articles, look at the names.