Tokyo, June 3 : A US military helicopter made an emergency off-base landing on a small island in Japan's southernmost prefecture of Okinawa, authorities said on Thursday. The incident, which occurred at around 11 p.m. on Wednesday, involved a UH-1 helicopter with five crew members aboard landing in a field on Tsuken Island due to engine trouble, the US military told the Okinawa prefectural police. No hazardous material was being carried by the chopper and none of the crew were injured in the incident, Xinhua news agency reported. The emergency landing did not damage the helicopter, which was made just 120 metre away from a house on the island. The island is home to just 380 people and located off the main island of Okinawa. The five crew members belonged to the US Marine Corps Air Station Futenma, local police official confirmed. Following the incident, the Japanese government set up a task force team on Thursday involving officials from the Foreign Ministry, the Defence Ministry and the Cabinet Secretariat to investigate the matter. Residents and officials in Okinawa have long been perturbed by numerous incidents of US military aircraft accidents and mishaps. Okinawa hosts the bulk of US military facilities in Japan, yet the tiny sub-tropical island accounts for just a small fraction of Japan's total landmass. Along with a steady flow of accidents and mishaps involving US military aircraft, Okinawa residents have also long-suffered from environmental and noise pollution. There have also been numerous cases of local citizens being victims of US base-linked workers' criminal activities. In addition, the planned relocation of the US Marine Corps Air Station Futenma from the densely populated city of Ginowan to a coastal region also in Okinawa, has deeply upset and angered locals and officials. They have long-called for their US base-hosting burdens to be lifted and for the Futenma base to be relocated out of Okinawa or Japan altogether. /IANS