Forest officials in Gujarat state in india have arrested about 18 lions over the past two months and were now being kept in separate cages so they can test the lions' prints and ecrement in an attempt to identify a man eater among them suspected of killing three people.
Six attacks on humans have been reported recently near the sanctuary, the only habitat of the Asiatic lion.
"We think we have pinpointed the guilty lion, but we are still awaiting the results of nine more animals," he said.
Wildlife expert Ruchi Dave told the BBC that the "tests" involved studying the pug marks and faecal matter of the lions.
"The officials are also studying the animals' behaviour. Man eating lions usually get aggressive at the sight of a human being," she said.
Another wildlife expert Revtubha Raizada said the man-eating lion would be caged for the rest of its life, as it was too unsafe to release it back into the wild.
Some experts feel that the thriving lion population in Gir forest is to blame for the "unusual" behaviour by the lions.
Govind Patel, the former chief wildlife warden of Gujarat, told the Indian Express newspaper that Gir could accommodate only 270 lions, forcing some prides to settle outside the boundaries of the sanctuary.
The "guilty lion" will be kept in a zoo for life while the others will be released back into the Gir sanctuary, the officials told BBC Hindi.