Read the entire post; it's there. Don't even have to go to the link.
Yes and no. It describes them as being Nortenos, but that is a whole collective of northern Mexican and Latino California street gangs, possibly numbering in the thousands, under who knows how many local “brands”.
And the issue is further confused because they said it was a “prison gang”. But there is not a clean overlap between street gangs and prison gangs. Allies on the inside might be enemies on the outside.
California gangs are difficult to police up, because they tend to be decentralized organizations. There are many “chiefs” and “braves”, like in an Indian tribe, but no hierarchy and no overall leadership. A chief is only a chief because a few braves will hang out with him for a while. He has no real authority over them.
The federals, state and local police spend a heck of a lot of time figuring out who is doing what to whom with gangs.