Mumbai, Nov 9 (IANS): Environmentalists have knocked the doors of Prime Minsiter Narendra Modi seeking an NIA probe into the killing of alleged man-eater tigress Avni (T1) in Maharashtra six days ago, with plans to file a PIL in the Supreme Court soon, activists said.

Simultaneously, Mumbai Congress President Sanjay Nirupam alleged that in the past one year or so, 21 tigers may have died in Chandrapur and Vidarbha region of Maharashtra for which he pointed an accusing finger at Forest Minister Sudhir Mungantiwar.

"In his (Mungantiwar's) regime, tigers are being killed/poached regularly in big number. Last year, 21 tigers were killed. Is he part of poacher mafia? Must be investigated," tweeted Nirupam.

A wildlife-focussed site, natureconnect.com, has written to Modi demanding a probe by the NIA and the NGO, Resqink Association for Wildlife Welfare (RAWW) has sought a CBI probe into the tigress' killing on Nov. 3.

Natureconnect's founder B.N. Kumar said the Prime Minister is the chairman of National Board for Wildlife and an impartial, unbiased probe by NIA would unearth facts about Avni's killing since in her case, the guidelines of National Tiger Conservation Authority (NTCA) were allegedly flouted.

Satpuda Foundation's Kishor Rithe said the investigations must probe in depth the man-animal conflicts in the Yavatmal forests since 13 human lives were lost in the region.

Karnataka-based veterinarian Prayag H.S. said Avni's two orphaned 11-month cubs must be secured immediately and said after the revelations in the tigress' autopsy report, he would move the Supreme Court. On the other hand, the Vasantrao Naik Sheti Swavalamban Mission (VNSSM) has blamed Union Minister Maneka Gandhi for adopting an "elitist, anit-tribal and anti-farmer stance" vis-A-vis Avni.

VNSSM Chairman Kishore Tiwari said that "the deaths of 13 tribals-farmers and the fears of around 100,000 terrified people living in the vicinity just cannot be ignored". His statement came amid demands made by Gandhi for the ouster of Mungantiwar from Maharashtra cabinet even as Chief Minister Devendra Fadnavis promised a probe into possible 'procedural lapses' in gunning down the tigress.

Claiming that the NTCA guidelines were adhered to, Tiwari said rampant breeding of tigers in the forests has led to territorial wars since the Pandharkavda Division is too small to support 10 tigers, hence they are spilling out of the forests into human settlements.