They were caught red-handed by police in Vinh Linh District transporting the bomb for sale on May 1. The cylinder-shaped object covered under a sheet of cloth was put on a trailer.
The 300-kilo bomb contains 185kg explosives
The American-made M177 bomb which had an intact fuse remained weighs up to around 300 kilos and contains roughly 185kg explosives.
The vehicle driver Le Van Ty, said that the bomb was found at a rubber plantation in Quang Tri Province earlier. The local police have also detained three other people involved in the case.
About 800,000 tonnes of bombs, mines, and other explosive weapons litter the country from the long-running conflict from 1954 to 1975.
All 63 provinces and cities in the country have been contaminated with unexploded ordnances (UXOs). Quang Tri is among the hardest-hit localities by these.
Since the war ended in 1975, the Vietnamese government has spent USD80-100 million attempting to address the issue every year and has received support from domestic and international organisations.