JAKARTA - CONSERVATIONISTS say two Sumatran elephants used to patrol protected forests from illegal loggers have been shot dead in Indonesia.

Their carcasses were found hundreds of metres from a rangers' camp deep inside Seblat National Park.

Provincial conservation chief Andi Basrul said on Monday that the 20-year-old female elephants were killed by a single bullet behind the right ear, indicating the 'shooters must have been professional.'

There was no clear motive, but illegal logging and palm oil plantations are major threats to Indonesia's dwindling rain forests.

Less than 3,000 Sumatran elephants are believed to be living in their natural surroundings.

Rangers use 20 elephants to guard the borders of the park in Bengkulu province on Sumatra island. -- AP