@OmNLSAABotACC
Basically, the publisher or author is warning the group to stop illegally translating and distributing their work, or else they will sue them.
There are a couple of ways around this, like hosting the manga on a server that is outside the jurisdiction of the legal authorities dealing with the problem (so let's say hosted on a server in Turkey while the author would be dealing with Korean authorities), but still, it's a hassle and it's pretty scary being on the receiving end of a legal action against you.
What mikoreimu is referring to is the Digital Millennium Copyright Act, which is basically the US version. I don't think this is what we're talking about, as I doubt any of this is happening in the USA, but who knows where KKJ Scans are actually located. And to be fair, every country has their own version of this, more or less similar to each other. Hopefully they're being careful, behind a VPN, and other security measures.
Usually, patching a few things and letting the steam float away makes everything better after a while, which is what I think we're seeing right now.