Dealing a serious blow to tiger poaching in the country, Delhi Police on Thursday arrested India's most wanted animal killer and smuggler Sansar Chand who allegedly had a major role in the disappearance of tigers in the national parks, including Sariska.

Nicknamed 'Veerappan of North India', 50-year-old Chand was nabbed from a house in Patel Nagar in west Delhi in a dramatic manner after a three-month-long operation, Delhi Police Commissioner K K Paul said.

"Only one name figures when the dwindling tigers in Sariska are discussed - Sansar Chand. He is a major catch for us," Paul said.

Chand had over 40 cases, under the Wildlife (Protection) Act, 1972, registered against him in Delhi, Rajasthan, Uttaranchal, Punjab, Uttar Pradesh, Madhya Pradesh, Karnataka and Andhra Pradesh.

He had been convicted twice in such cases, the last time being in April 2004 when a court in Ajmer sentenced him to five years' rigourous imprisonment. This was the strictest punishment ever awarded under the Wildlife Act.

In May, last year, Rajasthan High Court granted him parole, which he jumped and went underground. Besides the CBI, police in several states were hunting for him since then.

Even by conservative estimates, Chand is believed to be responsible for the poaching of hundreds of tigers.

Under the instructions of Prime Minister Manmohan Singh [Images], the CBI had probed the disappearance of tigers from Sariska, which revealed that Chand was the man primarily responsible.