Several million Snapchat usernames and phone numbers were apparently leaked online late Dec., 31, 2013. Several outlets reported that 4.6 million usernames and phone numbers were posted as a downloadable database by hackers, but the site where the database was posted appeared to be down on Wednesday morning, USA Today reports.

Days prior, Snapchat – a popular messaging app that lets users send each other photos that quickly disappear – warned users of this potential scenario in a blog post, saying a security group had alerted it about a potential vulnerability “by which one could compile a database of Snapchat usernames and phone numbers.” The company said that it had implemented safeguards making an exploit “more difficult to do.”