The 1.6m long bomb is believed to be dropped by US planes during the war. Local military officers have erected fences around the bomb while awaiting for sappers to defuse the UXO.
During the war, the US army dropped more bombs on Vietnam than were deployed in the First and Second World Wars combined, according to the US organisation Clear Path International (CPI).
It is estimated that as many as 30 percent of the bombs remain unexploded, equivalent to 800,000 tonnes.
Several decades after the war’s end, UXOs still kill and maim thousands of innocent people and greatly hinder economic development in the country.