Turns out the one spreading the rumors was Hashimoto, who did so at the behest of Sakayanagi. Shortly thereafter, Sakayanagi appears before Class C and she informs them she has evidence regarding the rumors about Ichinose.
I'm sure I have no idea 
what you're talking about.
لا أملك فكرة عمَّ تتكلّم عنه بالتأكيد
Mit mir hat das nichts zu tun.
Esos a mí no me conciernen.
Esos a mí no me conciernen.
Je n’ai rien à voir là-dedans.
Non da quello che so io.
Tenho certeza de que não
faço ideia do que está falando.
Не понимаю, о чём ты говоришь.
ตรงนี้ไม่ใช่เรื่องที่ฉันต้องรับรู้สักหน่อยค่ะ