The Sumatran rhino, the most endangered of all rhinoceros, is fast heading to extinction with its population at one of its last reserves in Indonesia dropping by 90 percent in 14 years to 50, an official said.

The director for forest protection and nature conservation at the forestry ministry, Widodo Sukardi, told the state Antara news agency the number of Sumatran rhinos at Kerinci Seblat national park (TNKS) was now down to about 50 from around 500 in 1990.

The TNKS is the country's largest national reserve, straddling four provinces on Sumatra island -- West Sumatra, Jambi, Bengkulu and South Sumatra. It is one of the last reserves for the small and hairy Sumatran rhinoceros.

The dwindling rhinoceros population of the park was mostly due to illegal hunting and poaching by people in Bengkulu and West Sumatra, a Bengkulu province official was quoted by Antara as saying.

The officials called on people in and around the TNKS to refrain from hunting the rare animal as well other wildlife in the reserve.

To keep the Sumatran rhinos from extinction, Sukardi said his office would relocate captured rhinos to a safer location in the Way Kambas National Park in Lampung province, also on Sumatra.

The International Rhino Foundation has estimated there are fewer than 300 Sumatran rhinos surviving in very small and highly fragmented populations in Southeast Asia with Indonesia and Malaysia being home to most.