Yep Mex National is a PC way to say “ilegal”. If he was a US citizen there would be no description like that...or if he was legal. Most of that Mission area is Hispanic
Do you really think the police -- let alone the press -- can confirm someone's immigration status within a day of an arrest? The absence of some details in an initial story isn't always proof of political correctness or some sort of "MSM blackout." Most of the time, they're omitting details they don't have.
Is this guy an illegal? Most probably. But most probably isn't good enough for the police to make a statement or for a reporter to put it in print.