A Zimbabwe court on Wednesday sentenced a poacher to more than 15 years in prison for poisoning and killing elephants with cyanide, the fourth such conviction in the country in a month.

The court in the western town of Hwange also found Akim Masuku, 26, guilty of illegal possession of ivory, handing down a total jail term of 15-and-a-half years, the Zimbabwe Parks and Wildlife Authority said in a statement.

The accused still faces separate charges for cyanide possession and for contravening environmental laws, wildlife officials said.

The case comes a day after the Parks and Wildlife Authority said 100 elephants had been killed by cyanide for their ivory in a single national park in just over a month.

"One hundred elephants have died in Hwange National Park due to cyanide poisoning and 12 people have since been arrested and four have been convicted and sentenced," it said.

Masuku's co-accused Norma Ncube, 18, is set to appear in court on October 30.

Three other poachers were in September sentenced to a minimum of 15 years each for poisoning 81 elephants.

They were also ordered to pay $600,000 (440,000 euro) to the wildlife authority for killing the animals.

Officials have given villagers living around the park until the end of October to hand over any cyanide they might have or risk arrest.

There are more than 120,000 elephants roaming Zimbabwe's poorly policed national parks.

Elephant tusks and other body parts are highly prized in Asia and the Middle East for ornaments, as talismans and for use in traditional medicine.