HO CHI MINH CITY, Oct. 1 (Xinhua) -- A 105-mm shell exploded in Vietnam's southern Ca Mau province on Monday, killing three local people in one family, and injuring two others, the provincial police said.

The explosion in Tran Van Thoi district killed a 52-year-old repairman, his daughter-in-law and his granddaughter, and injured Thang's wife and his neighbor, a 31-year-old woman.

The explosion occurred when Thang was welding a faulty diesel engine near the shell, a provincial police officer said, noting that the repairman found the shell years ago and brought it home, using it as an anvil.

During the Vietnam War, the U.S. Armed Forces deployed more than 15 million tons of bombs, mines, artillery shells and other ordnance in Vietnam, in which 10 percent did not detonate as designed, according to the Vietnam Veterans Memorial Fund of the United States.

Vietnamese scrap collectors often saw unexploded ordnance for metal and explosive, while small children play ammunitions by breaking them, resulting in hundreds of deaths and injuries annually.