Ultimate Warrior Dies At Hotel -- Clutched Chest & Collapsed ... Witnesses Say

The Ultimate Warrior "clutched his chest" moments before he collapsed at an Arizona hotel Tuesday afternoon ... this according to law enforcement sources who spoke with witnesses.

TMZ has learned ... Warrior was walking down a hallway at the Gainey Suites Hotel in Scottsdale, AZ and headed toward his car with his wife -- when he stopped, clutched his chest and went down.

We're told Warrior never recovered.

Sources connected to the situation tell us officials believe Warrior suffered a "catastrophic medical event" and so far, we're told there is no evidence to show drugs or alcohol were a factor in his death. All signs point to massive heart attack.

We're told an investigation is underway. The Maricopa County Medical Examiner tells us the autopsy is scheduled for Thursday.