By KRISTA LARSONDAKAR, Senegal (AP) â¿¿ Apple, Hewlett-Packard and Intel have become "pioneers of progress" through their efforts to avoid purchasing minerals that fund armed groups in Central Africa, an advocacy group said Thursday. The Enough Project ranked companies based on the steps they have taken to make sure their mobile phones, iPads and other gadgets aren't paying for the weapons used to terrorize Congolese civilians. The group's advocacy was instrumental in pushing through U.S. legislation that has caused a dramatic decline in the minerals trade from embattled areas of the Congo. However, the reduction in exports hasn't led to a corresponding decrease in violence â¿¿ eastern Congo is in the grip of a fresh rebellion, and 280,000 people have fled their homes since April. Congo is home to about 70 percent of the world's supply of tantalum, a metal used in cellphones, according to the U.S. Geological Survey. The vast country also has massive amounts of tin, gold, copper and cobalt. Although most of the companies had shown improvement since 2010, the Enough Project cited video game console maker Nintendo Co. as trailing behind the rest of the industry when it comes to "conflict minerals." Armed groups vying for control of these riches have used profits from illegal mining to purchase weapons used in gruesome attacks on civilians. In other cases, they have captured people and forced them to do the digging. "The exploitation of Congo's mineral resources continues to exacerbate conflict and instability on the ground and consumers are still largely in the dark as to whether or not their products are conflict free," the report said. The idea that mining exacerbates the Congolese conflict is controversial. Many experts say the real problem in eastern Congo is the lack of a functioning government, not that there are valuable minerals there.