Vietnam War-era shell kills four children The children, a girl and three boys aged between four and 11-years-old, died on Sunday after finding the unexploded shell while they played in a garden, according to police officer Luong Van Tri. Four others - two men and two children aged five and 12 - were seriously wounded in the blast which occurred in Vinh Long province, he added. The owner of the house found the US-made 81-millimetre (3.2 inch) shell several years ago. He left it next to bamboo trees in his backyard garden without reporting it to authorities," Tri told AFP. "The kids lifted the shell and threw it, triggering the blast," he said, explaining that the adults had been indoors and had not seen the children playing with the device. Vietnam's communist government said in May that at least 42,100 people had been killed and 62,100 others injured due to war-era bombs and mines since the conflict with America ended in 1975. Authorities have said they need more than $1.6 billion to clear about 1.3 million hectares (3.2 million acres), 20 per cent of the nation's land, which is contaminated by unexploded munitions.