(IDEX Online) - Fifteen workers have died so far this year and more have been injured in accidents mining for gold and other precious metals in Zimbabwe, says a union boss.Justice Chinhema, general secretary of Zimbabwe Diamond and Allied Minerals Workers Union (ZDAMWU) says many mines are increasingly unsafe. Ten fatalities were at small scale mines, he said. Five were at larger operations."We are worried that most mines are not safe, many abandoned mines have been heavily panned by artisanal miners and we have seen the weakening and ultimate destruction of pillars," he told the New Zimbabwe website.He called for better regulation of small-scale and artisanal mines, in the hope that it would cut the accident toll.