One of Africa's oldest national parks is under attack "from all fronts," its director has said, after 68 elephants were slaughtered in two months by poachers, some of whom shot them from helicopters.

Garamba National Park in the Democratic Republic of Congo is under constant assault by renegade Congolese soldiers, gunmen from South Sudan and others. Several bands of poachers have killed 4% of its elephants since April. Conservationists say a thriving ivory market in Asia is helping to fuel the poaching epidemic.