New government estimates show that killings of South African rhinos for their horns has increased 50 percent since 2011 and nearly 5000 percent since 2007, according to the group, marking a new peak.

Last year, 668 rhinoceros were killed illegally in South Africa for their horns, a new high, according to the World Wildlife Fund, which studies wildlife poaching and illegal animal trade.

New hunting methods for the nearly 2,000-pound (900 kg) animals, including high-powered rifles, helicopters, and night vision goggles have eclipsed more traditional hunting tools such as bows, arrows, and spears. (Read “Blood Ivory” in National Geographic magazine“Blood Ivory” in National Geographic magazine“Blood Ivory” in National Geographic magazine.)

“The African rhino is under serious threat from poachers