KINSHASA, Democratic Republic of Congo, Nov. 22 (UPI) -- Park rangers in the Democratic Republic of Congo say they've returned to a rebel stronghold to protect endangered mountain gorillas from slaughter.

The Virunga National Park contains nearly a third of the world's estimated 700 remaining mountain gorillas, The Times of London reported Saturday.

For years, the forest has been controlled by Hutu militias and rival Tutsi rebels who fled Rwanda after the genocide in 1994, the Times reported. Tutsi rebels seized the park headquarters last month, causing 240 park rangers to flee.

After negotiating with the rebels, some of the rangers returned this past week, gaining entrance to the park headquarters and to areas of the national park they had not been able to visit in more than a year, said Ranger Dusabimana John.

"I was worried about the gorillas and elephants," John said. "If we are not here then no one can stop them (from) being killed."

Downplaying the risk to their own safety, park rangers said they convinced the rebels of the importance of the park as a world heritage site of global significance, said the park's director, Emmanual de Merode, calling the negotiations a "huge breakthrough."

"It's the presence of all these armed groups, the chaos and people who simply need to make a living that's destroying the park along with a future for tourism and conservation here," de Merode said.