MJ tomb defaced

Michael Jackson's tomb has been defaced by a stealth band of vandals -- who have marked the walls of MJ's mausoleum with hidden messages ... and it's all in permanent ink.

Security at the tomb is on the lookout for "fans" who have been writing messages in hard-to-spot places outside the main window of the building in which MJ is entombed.

The writing is mostly hidden underneath ledges -- or in spots covered by bushes -- and contains messages like, "Miss you" and "Keep the dream alive."

Now that’s what you call writings on the wall.