Very much so. Diving in nearly the same area, I once (unbelievably) had a private dive boat decide that my dive flag was the one their diver had abandoned earlier. They came by, grabbed it, gunned the engine to break it loose from where it was supposedly hooked to the reef, and drove off with it while my dive boat was blowing its horn, shouting over the loudspeaker, and heading for them at full speed. When I felt myself heading to the surface with the flag, I decided to let go of the flag rather than take an unexpected ride in their wake. With no flag, I simply sent up my DSMB and went on with the dive.
Wtflol