The level of metals sourced from war-torn areas of the Democratic Republic of the Congo and used in electronics has decreased, an advocacy group said. The purchase and use of these metals -- tin, tantalum, tungsten and gold -- in so-called \"blood phones\" and other electronics helps fund armed forces in the Congo, who often force people to work in the mines at gunpoint for little or no money, advocacy group Free the Slaves said. A report by the advocacy group Enough Project said most technology companies have made a better effort to verify their raw metals are conflict free since its previous evaluation in 2010. Intel, HP, Dell, Microsoft and Apple received the highest scores in the report by the group while Nintendo, Canon, Nikon, Sharp and HTC received low rankings, CNN reported Thursday. Nintendo received a score of zero for failing to follow any of the suggestions made by the Enough Project. \"Nintendo is, I believe, the only company that has basically refused to acknowledge the issue or demonstrate they are making any sort of effort on it,\" said Sasha Lezhnev, senior policy analyst at the Enough Project. \"And this is despite a good two years of trying to get in contact with them.\"