As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE FOR KTYS TO KLGA THE LEFT THRUST REVERSER UNLOCKED CAUTION MESSAGE ILLUMINATED. THE FLIGHT CREW PERFORMED THE QRH AND DECLARED AN EMERGENCY. THE AIRCRAFT WAS DIVERTED TO KIAD. AN OTHERWISE NORMAL APPROACH AND LANDING WAS MADE AT KIAD. MAINTENANCE INSPECTED THE LT THRUST REVERSER AND REPLACED THE LT ENGINE THROTTLE CONTROL GEARBOX. THE AIRCRAFT WAS RELEASED FOR SERVICE.