Wed December 16, 2020 - West Edition #26 Associated Press YUMA, ARIZ. (AP) A construction crew in southern Arizona has discovered an unexploded howitzer round while working on a road. Yuma Proving Ground's explosives experts identified the ordnance as a 155 mm howitzer round of a kind that were used in World War II and the Vietnam War, The Sun reported. The round found on Martinez Lake Road during an $18 million improvement project that began in February was the second discovered this year. The first was found in April in the same location. Martinez Lake Road was closed for several hours while crews worked to remove the round, authorities said.