A mine collapse at a major coltan mining site in eastern Congo left at least 200 dead, according to Congolese authorities, a number disputed by the rebel group that controls the mine. The collapse took place Tuesday at the Rubaya mines, which are controlled by the M23 rebel group, Congo’s Ministry of Mines said in a statement on Wednesday. It was the latest such tragedy in the mineral-rich and rebel-controlled territories of the country. But senior M23 official Fanny Kaj disputed the figure,