Maty, Kazakhstan, Feb 20, SPA -- A military shell sold as scrap metal exploded and killed five workers in central Kazakhstan, the emergencies agency said Monday. The blast occurred Saturday at a workshop in the central town of Balkhash, 550 kilometers (342 miles) southeast of the capital Astana, when the workers were cutting the shell that had been sold to them as scrap metal, the regional emergencies agency said. It said it could have been a tank shell from some abandoned military facility. Several more shells of various caliber were found at the site of the blast, the agency said. There is a military unit located near Balkhash. The incident is being investigated, the Associated Press quoted the emergencies agency as saying.