Today a new Locky Ransomware variant was discovered that switches to the .lukitus extension for encrypted files. It is not currently known how this variant is being distributed, but as the ransomware is being downloaded from a remote site it is most likely malspam. […]

from https://www.bleepingcomputer.com/news/security/locky-ransomware-switches-to-the-lukitus-extension-for-encrypted-files/