Two years after the controversial hunting death of Cecil the Lion, authorities at the Zimbabwe national park where he lived are still struggling to protect the wildlife there.

In the latest incident, a group of poachers was caught on Thursday killing elephants and removing their tusks at the Hwange National Park. One of the poachers—out on bail while appealing an illegal hunting conviction—was shot dead by park patrol, while another was injured and captured over the weekend after fleeing the scene, according to updates from the nonprofit conservation group Bhejane Trust, which monitors the park.

Two elephants were killed, and two more poachers remained at large. The poachers weren't named.

“There is some controversy on the ‘shoot to kill’ policy,” Bhejane Trust said in an update on Facebook, referring to the park’s policy of shooting poachers on sight. “But these ivory poachers ... would not hesitate to shoot if confronted by rangers. It is basically a war, and there is no reason for the rangers to expose themselves unnecessarily.”

The shooting is the latest in a string of incidents at Hwange since one of its most famous residents, a 13-year-old black-maned lion named Cecil, was shot just outside the park by a trophy hunter in July 2015. While that hunt was deemed illegal, it sparked a debate over legal big-game hunting as well, which proponents argue supports conservation efforts by raising money. Lion populations have declined 43 percent over the last two decades, according to the U.S. Fish and Wildlife Service.

Charges against the professional hunter who helped Minnesota dentist Walter Palmer kill Cecil were dropped in 2016, and Palmer himself never faced charges despite calls to extradite him. Palmer reportedly paid $54,000 to bow-hunt Cecil.

Australia and France flat-out banned the import of lion trophies in the wake of Cecil's death, while the United States instated new restrictions dictating that any imported lion trophy must come from a country that uses hunt fees to support conservation, adding that permits for countries including Zimbabwe were under evaluation. Zimbabwe, for its part, suspended big game hunting for 10 days and then restored it. (Read more about what happened in the year following Cecil's death.)

And last month, Bhejane Trust reported that a total of 10 elephants had been poisoned near the park over the course of a few days, another instance of poachers using black-market cyanide to cheaply and quietly kill elephants for their ivory tusks. An elephant population survey released last year found that populations in Africa are shrinking eight percent annually.

The captured poacher at Hwange has named the accomplices who escaped from the latest killings, Bhejane says, and "more arrests can be expected."