Manti Te'o Scandal -- Notre Dame Tells Staff KEEP YOUR MOUTHS SHUT

Notre Dame is circling the wagons on the Manti Te'o not-really-dead-girlfriend hoax ... TMZ has learned the school has instructed staff to keep their mouths shut ... or else.

One person connected to the program tells us ... officials have warned staff, if they speak to the media about the scandal without permission from the University, they will "never work for Notre Dame again."

The ND athletic director already held a news conference last night, saying the University believes Manti is an innocent victim who was hoaxed by some cyber-bullies for no apparent reason.

The initial article published by Deadspin.com suggests Manti may have been involved in concocting the hoax in an effort to gain publicity on a national level.

Manti is expected to address the media later today.