India has far fewer tigers living in the wild than had been thought, initial results from a major new study suggest.
There has been a sharp decline in the number of tigers in India
The Wildlife Institute of India census showed tiger numbers falling in some states by two-thirds in five years. A final report is due out in December.
India's last major survey in 2002 put tiger numbers at 3,500. That was far too optimistic, say conservationists.
They blame poaching and urbanisation for the decline and say the authorities must do more before time runs out.
A century ago India was believed to have tens of thousands of tigers.
The new survey, conducted over two years, was the most ambitious ever undertaken to try to stem the decline in the population of India's tigers.
It found the largest decline in the tiger population to be in the central state of Madhya Pradesh, where the number of big cats has gone down from 710 to 255 in the past five years.
Tiger skins and other body parts sell for thousands of dollars
"The figures are quite different from what we have seen earlier," said Mr Rajesh Gopal, secretary general of the government's Tiger Conservation Authority of India, which also took part in the survey.
Mr Gopal said the new study was far more detailed than any previous research.
Results are available only for some regions and a total overall figure is not expected until later this year.
But conservationists say the 2002 census badly overestimated tiger number.
Wildlife experts have criticised the Indian government for failing to crack down on poachers and the illegal trade in tiger skins.
"The results are depressing," Belinda Wright, director of the Wildlife Protection Society of India, told the Associated Press news agency.
"But it's a major step forward that a government study has finally come to terms with this disastrous decrease in tiger numbers," she said.
According to reports, there were 40,000 tigers in India a century ago.
The country is home to 40% of the world's tigers, with 23 tiger reserves in 17 states.
Tigers are poached for their body parts - skins are prized for fashion and tiger bones are used for oriental medicines.
Tiger pelts can fetch up to $12,500 in China.
Some conservationists say forest officials often inflate the number of sightings to paint a rosy picture of how India's tigers are surviving.
Tiger expert Valmik Thapar says the government has failed to protect its tigers.
He says instead of wasting time and energy on carrying out the new survey, the government should concentrate instead on protecting tigers.