For some reason, vicious rumors demonizing foreigners were spread after the 2011 quake in northern Japan but, for the most part, not after the Kumamoto earthquake. After the quake here, a lion, not a foreigner, became fodder for fake news:

“In the wake of the Kumamoto quakes in April last year, police arrested a man on suspicion of fraudulent obstruction of business over a fake photo and tweet indicating that a lion had escaped from Kumamoto City Zoological and Botanical Gardens.”

– Kirk

http://mainichi.jp/english/articles/20170313/p2a/00m/0na/010000c#csidxd470bc93df5ac05aa89c441e75c013e

P.S. I learned about this article on debito.org. If you are interested in human rights issues in Japan, you may want to check it out.