What was found
WHILE AT CRUISE, TECHNICIAN NOTICED A BURNING SMELL, WITHIN A FEW SECONDS SMOKE BEGAN TO FORM IN THE BACK OF THE AIRCRAFT. PIC DIRECTED EVERYONE TO DON OXYGEN AND RUN APPROPRIATE EMERGENCY CHECKLIST. CREW DECLARED EMERGENCY WITH ATC AND BEGAN VFR DESCENT TO CLOSEST SUITABLE AIRFIELD. LANDED UNEVENTFULLY WITHIN APPROX 5 MINUTES OF THE EMERGENCY. CLEARED THE RUNWAY AND EVACUATED AIRCRAFT. SOURCE OF SMOKE UNDETERMINED AT THIS TIME.