From Krebs On Security:

Sometime in the last 24 hours, truecrypt.org began forwarding visitors to the program’s home page on sourceforge.net, a Web-based source code repository. That page includes instructions for helping Windows users transition drives protected by TrueCrypt over to BitLocker, the proprietary disk encryption program that ships with every Windows version (Ultimate/Enterprise or Pro) since Vista. The page also includes this ominous warning:

“WARNING: Using TrueCrypt is not secure as it may contain unfixed security issues”

“This page exists only to help migrate existing data encrypted by TrueCrypt.”

“The development of TrueCrypt was ended in 5/2014 after Microsoft terminated support of Windows XP. Windows 8/7/Vista and later offer integrated support for encrypted disks and virtual disk images. Such integrated support is also available on other platforms (click here for more information). You should migrate any data encrypted by TrueCrypt to encrypted disks or virtual disk images supported on your platform.”