Unsettling message spotted on Google Earth, "HELP," "TRAFICO,"

From a Facebook google earth group: Unsettling message spotted on Google Earth near Cesar Chavez Ave, LA: "HELP," "TRAFICO," "LAPD," and "FEDERAL" written in debris Coordinates: 34°03'17.8"N, 118013'32.2"W.

You can see what looks like a tunnel.. and it’s near cargo storage/railroad. Anyone know about this?