A national treasure trove of rare books, manuscripts and letters associated with Rabindranath Tagore, Netaji Subhas Chandra Bose, Sarat Chandra Chatterjee and Sarojini Naidu may have been stolen from Kolkata's National Library.

Worse, there's no way to know what exactly is missing, since the register containing records of the library's Rare Books Division itself is untraceable.

The rare collection contains Tagore's early works, letters of Netaji, manuscripts of Sarat Chandra and Bibhuti Bhushan Bandopadhaya, besides many valuable books from the 18th century and earlier. In fact, at least 40% of books and documents requisitioned by members from the entire library were reportedly not found, sources said.

An investigation has been launched into the missing books and other collectors items after the "theft" came to light during a routine examination of the accounts and functioning of the library by the Comptroller and Auditor General (CAG).

The premier auditing agency, sources said, constituted an 11-member team to investigate irregularities, especially to look into the missing treasures.

Sources said CAG has written to the culture ministry seeking immediate action against the director of the library who failed to provide details of the resources available at the centre. CAG, in its missive to the culture ministry, said that the entire library was in a mess and no inventory was available for most of its departments.

The library, one of its kind in the country, has a large collection of rare monographs, manuscripts, microfilms and other pieces of history, including the official documents from the days of the East India Company.

Other riches in the Rare Books Division include maps dating to the 17th century, xylographs presented by the Dalai Lama, collection of Burmese documents besides papers relating to Aden, Ceylon and the Persian Gulf.

Sources said the library management was found to be lax in procurement of important contemporary books from across the world relating to India, much against its mandate. In 2004, about 60,000 books on India-related subjects were published. But the National Library obtained only 6,000 titles. As per the rule, it has to ensure a copy of all published works on India-related subjects.

With more than a Rs 20-crore annual budget and 500 employees, the library is yet to recruit experts on many foreign languages. It received books in 56 languages in the past few years but had experts on only five languages — Russian, Persian, Chinese, German and Arabic. Rest of the books and vital pieces of Indian history, published in other languages, have been allegedly dumped in storehouses.

The inquiry has revealed financial irregularities too. Records show the library management had availed of only 10% discount whereas nearly 20-25% discount is the market norm, the probe team observed.

The CAG had set a deadline of July 28 for the library management to provide all details of the actual stock of the library and the missing items. However, sources said, only 1% of the records was made available by the director to the 11-member inquiry committee after which CAG called off the probe and sought the intervention of the culture ministry.