An explosion causing big fire killed four students and injured another one in Vietnam's southern Ho Chi Minh (HCM) City on Saturday afternoon, local media reported. Accordingly, around 2:30 pm local time (GMT 0730) on Saturday, three consecutive explosions were heard coming from a house on Ly Thuong Kiet Street in district 10 of HCM City, and soon after a big fire came out from the second floor of the house, local online VNExpress reported. Some local residents tried to extinguish the fire but in vain, until fire fighters from district 11 near the spot came and controlled the fire in about 30 minutes, said the report. The accident killed four students on the spot and injured another one who was brought to Trung Vuong Hospital in critical burning condition. Lieutenant-colonel Huynh Quang Tam, chief of District 1 Fire Prevention and Fight Station told local media said the victims are students of the HCM City University of Technology, which is located near the explosion site. According to initial reports from local residents and friends of the victims, those five students were making firecrackers for use in the coming Tet holidays when the blast broke out. The students shared a room on the second floor of the house. Two days earlier, one of them was seen brought from the market explosive chemicals for firecracker making, reported local online news portal Tuoi Tre.