In a disturbing development in the ongoing killing of wild African animals for profit, poachers in Zimbabwe’s largest game park have poisoned more than 300 elephants and other animals using cyanide, according to the Zimbabwe Conservation Task Force.

Conservationists have called the mass killings the single worst massacre in southern Africa in the past 25 years, the Telegraph reports. Pictures of the dead animals have been shared by the news outlet, showing deflated corpses of elephants from Hwange National Park.

“In July, around 300 elephants had died from cyanide poisoning in Hwange and were discovered by a group of hunters who flew over the area,” Johnny Rodrigues, chairman of the Zimbabwe Conservation Task Force, told the Agence France-Presse. “The authorities only stepped in in September, and by then the numbers had escalated. As of last week, about 325 had died altogether.”

Cyanide poisoning, a method first revealed in July, may be more widespread than previously thought. While Zimbabwean authorities say 100 animals have been killed by poisoning the animals’ watering holes and salt licks with the deadly chemical, hunters who have surveyed the area and took the photos say they counted more than 300 animal carcasses.

Sources say government officials have been threatening villagers, offering money to buy their silence on who the poachers are, The Standard reports. Rodrigues adds the government is downplaying the numbers in order to protect a sophisticated network of poachers that may include top government officials and law enforcement agents.

“The problem is that a big cover-up is going on,” he said. “Those who have been arrested and convicted are the small fry who are being used as scapegoats while the big and dangerous fish are untouched. These include politicians and big business people.”

Thamsanga Mahlangu, Zimbabwe’s shadow minister of environment and natural resources, says the poachers may be connected to the ruling political party of the country, known as Zanu PF, wildlife authority officials and the police. He claims that some villagers were paid “as little as US$500” to poison the elephants' water wells.

Some villagers have been arrested and jailed for at least 15 years. One villager said his son was recently sentenced to 16 years and fined $200,000 for poisoning the elephants.

"We are victims of poverty. My son is in jail because we are poor people," Linah Tshuma told the Times of Zambia. "I don't know what happened but he was employed by a businessman, who I believe was the one dealing in ivory because he is on the run."

Tshuma is a member of the San people, an indigenous population living in western Zimbabwe that have been blamed for the elephant slaughter.

"Poverty is the problem here," Christopher Dube, a vocal member for the San community, told the Times of Zambia. "Poachers target our people because they know they are poor. We are told that people were promised US$20 per tusk."

Police have told villagers they must hand over any cyanide in their possession by the end of the month in order to avoid arrest.

"We were given a month and we do not know what will happen after that. Maybe the police will come and arrest us all or they will come and beat us up," Sihle Ncube, a villager who lives near the park, said. "We are living in fear and a number of villagers are thinking of crossing into Botswana before the ultimatum is up."

According to the International Fund for Animal Welfare and the World Wildlife Fund, the often illegal ivory trade has experienced a surge of elephant slaughters – with 30,000 African elephants killed each year. The surge could be blamed on growing demand for ivory in Asia and the United States, CNN reports.

"Rangers are regularly killed by poachers, and some of the world's poorest countries continue to see their wildlife decimated for the black market in wild animals and parts,” The International Fund for Animal Welfare, wrote in its major study on the illegal wildlife trade published in June. “ Meanwhile, the profits realized from the illegal trade in wildlife have surged to levels once reserved for legally traded precious metals.”