Netherlands East Indies Forces Intelligence Service (NEFIS) was a Dutch World War II-era intelligence and special operations unit operating mainly in the Japanese-occupied Netherlands East Indies (now Indonesia).
That was the task of the Inter-Allied Services Department (ISD), which was set up in April 1942 on the instructions of US General Douglas MacArthur, and was responsible for sending out agents to commit sabotage and gather intelligence in occupied areas.
It sent secret agents into occupied territory by submarine or plane to gather intelligence on the local political and military situation.
If possible, these agents had to make contact with the local population to gather information and set up undercover organisations.
It was also difficult to win support from the local population in the Dutch East Indies, as they feared Japanese reprisals.