Border Patrol agents assigned to the Brian A. Terry Station discovered unexploded WWII-era ordnance near the Arizona-Mexico border. The unexploded round appears to have become unearthed during recent rains in the southeastern Arizona desert.

A Border Patrol agent discovered the unexploded antitank round during a patrol along the Arizona-Mexico international border in Cochise County on July 20. The agent contacted Cochise County Sheriff Mark Dannel’s Office to get assistance in securing the area until an expert could make the round safe, according to Tucson Sector officials.

A U.S. Air Force explosive ordnance disposal technician from Davis Monthan AFB traveled to the site on Tuesday morning and confirmed the device was indeed a live round. The airman determined that the round could not be safely moved and decided to detonate it in place.

Border Patrol officials told Breitbart Texas that the MK2 37mm round appears to have been unearthed during recent rains. The round could have been in the area for nearly 75 years.

UXOInfo.com describes the round as a “high-explosive shell” that weighs about 1.6 pounds.

The round was designed for the M3 37mm antitank gun, WarfareHistoryNetwork.com stated. The design of the weapon began in the 1930s as the U.S. Army searched for an effective weapon to utilize against tanks. Testing of the cannon began around 1937. U.S. factories produced more than 18,000 of the weapons by 1943. The cannon could fire at a rate of 25 rounds per minute. The round became ineffective against German tanks soon after, but the cannon continued in use throughout the war in both Europe and the Pacific theaters. It proved to be highly effective against Japanese tanks, the author stated.

The discovery of the unexploded round in southern Arizona provided officials at the local and federal levels an opportunity to work together to safely remove the public threat. Officials urged anyone finding a suspicious or dangerous explosive device to not touch it and to contact authorities right away.