The popular X account for the “Sesame Street" character Elmo began posting controversial messages that were quickly deleted after going viral on Sunday.

"Elmo's X account was briefly compromised yesterday by an unknown hacker who posted disgusting messages, including antisemitic and racist posts. The account has since been secured," a spokesperson for Sesame Workshop, the nonprofit educational organization behind Sesame Street, said in a statement to ABC News on Monday.

Elmo's X account faced hacking. The account broadcasted antisemitic messages. The messages included hateful language. The incident shocked social media users. Screenshots of the posts circulated widely.