How do you know they are/were hackers?
I lost over a years worth of wordpress articles due to what I thought may be hackers… turned out to be a bad WP Plugin that corrupted my SQL database and that is where I lost my stuff.
It looked like hacker work due to a constant forward of all my landing pages to some stupid site. However I later figured out that it was a malicious wordpress plugin (kind of like a virus from an infected file) that took over my site.
So in theory, you could also say I got hacked into when in reality…. it was just a virus.
If you use any kind of SQL, you may want to look into this.