Today China - as an emerging economic colossus hungry for raw materials - is back in Zambia as a direct investor. Like past foreign patrons, the Chinese are taking no chances with their new prize. In July six workers at the Chinese-owned Chambishi mine were shot and wounded after rioting over wages...Labour relations [at the mine] have recently improved since the implementation of a new collective bargaining agreement...In April 2005 a massive and still unexplained blast levelled an explosives factory on the [same] premises, owned by China's NPC Mining Africa, killing 46 people...Chinese investors have also been criticised for deploying poorly-paid and under-equipped Zambians in dangerous jobs. In June Zambian authorities closed the Chinese-owned Collum Coal Mining Industries, based in southern Zambia. This followed reports that workers were being sent underground without protective clothing or boots.