Gunmen have killed six rangers in Virunga National Park, a UNESCO World Heritage Site in the restive east of the Democratic Republic of the Congo. Al Jazeera reports that here was no immediate claim of responsibility for the attack on Sunday morning but officials blamed Mai-Mai fighters, members of one of the dozens of armed militias battling for control of the country’s mineral-rich eastern borderlands. This latest attack brings to 200 the number of armed park rangers who are estimated to lost their lives in attacks going back more than 10 years.