In 2017, the red imported fire ant (RIFA), Solenopsis invicta, was discovered for the first time in Japan at several locations, mainly ports and harbors.  While “killer ants” were widely spoken about in the major media causing panic, I was trying to correct wrong and/or exaggerated information concerning this ant. The most important point is that in Japan no wild colony has been found except for inside container yards, thus the establishment of a wild population of RIFA has not been confirmed yet. This suggests that the RIFA invasion status of Japan is the initial state. I discuss measures needed at this invasion state. People sterilizing backyards and house gardens are just killing native ants, which can promote the invasion of RIFA. On the other hand citizen science can help find wild colonies in the places where official inspections do not cover.