In a sprawling tiger reserve in northeastern India, once upon a time poachers have become the tiger's best friend.

The 500-sq-km Manas National Park in western Assam was at one time a haven for militants as well as poachers who hunted tigers, rhinos and elephants. Today the tiger is roaring again at the park. And the elephants too have got a new lease of life.

Not long ago, Budheswar Boro roamed the grasslands hunting wildlife at ease. He admits he has killed scores of animals, including rhinos, elephants and a tiger.

A much feared poacher, Boro's life has since been transformed. He still roams the park with a gun, but for a cause.

"I now patrol the park looking for poachers. I feel sad when I look back at my past when I hunted animals," Boro said with a sense of remorse. "Today, the park is free from poachers and militants."

Like Boro, there are a dozen more poachers who guard the park in their changed role as custodians of wildlife.

It became possible after the park authorities launched a drive to woo poachers with financial incentives. The larger 2,837 sq km tiger reserve - encompassing the Manas National Park - was plundered by tribal Bodo guerrillas for almost a decade.

This prompted Unesco to list Manas as a World Heritage Site in Danger. "From the brink of collapse to a situation when the animals can breathe easy, Manas is on a comeback trail with a marked improvement in the overall situation during the past one year," says a park warden.

Manas is good news for India where the tiger population - estimated to be over 3,000 - has dwindled rapidly in the last few years.

In the past decade, up to 200 animals were slaughtered inside Manas, either by militants for food or by organised poaching gangs, says a park official.