The aircraft that attacked the Allied Group belonged to the Kanoya Kokutai and the TakaoKokutai. (Kokutai translates to "Air Group").
There were 27 Mitsubishi G4M1 Model 2's (codename "Betty") bombers belonging to the Kanoya Kokutai.
There were 9 Mitsubishi G3M2's (codename "Nell") bombers belonging to the Takao Kokutai.
These aircraft operated from the airfield on Kendari, Celebes. This is modern-day Sulawesi.
One source states that the aircraft that actually attacked the USS Marblehead were seven G3M2 "Nells" of the Takao Kokutai.
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