JOHANNESBURG (AP) — The South African government is reporting progress in the fight against rhino poaching.

The environmental affairs ministry said Wednesday that poachers killed 769 rhinos last year, a 25 percent decrease from the number killed for their horns in 2017.

Authorities attribute the decrease to better security and other nationwide efforts to protect rhinos. The new data shows fewer rhinos killed in most provinces in South Africa, home to most of the world's rhinos.

However, some conservationists speculate that the killing in past years has reduced poaching opportunities for traffickers.

Vietnam and China are key illegal markets for rhino horn. Some consumers believe it cures illnesses if ingested in powder form, although there is no evidence that the horn, made of the same substance as human fingernails, has medicinal value.