As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN PRESS LO ANNUNCIATOR ILLUMINATED IN FLIGHT APPROXIMATELY FL280. FOUND MAIN ENTRANCE DOOR WEATHER SEAL TO BE CUT AND FOLDED OVER. REMOVED SEAL AND INSTALLED NEW SEAL. PERFORMED SATISFACTORY OPS AND LEAK CHECK OF DOOR SEAL OPERATION. ALL WORK PERFORMED IN REFERENCE WITH HAWKER 400/400A MM 52-10-00 AND 21-30-00. NO DEFECTS NOTED AT THIS TIME. AN EMERGENCY WAS DECLARED.