EXCLUSIVE

Paris Jackson left a suicide note and then cut her arm with a meat cleaver ... TMZ has learned.

Sources with an intimate knowledge of the situation tell TMZ ... Michael Jackson's daughter called a suicide hotline and the person on the other end was alarmed enough to call 911.

Our sources say in addition to cutting her right forearm, Paris had taken a large number of Motrin pills.

We're told once Paris was taken by stretcher to an ambulance and then transported to a nearby hospital, she was placed under a 5150 psychiatric hold for 72 hours.

She received "numerous stitches" for the cut.

As for the suicide note ... we do not know what she wrote.