The news comes just weeks after India's billionaire Burman family, which founded consumer goods conglomerate Dabur, announced plans in September to raise its stake to take control of Religare by investing $255 million.

Religare's former owners, brothers Malvinder Singh and Shivinder Singh, resigned from the board in 2018 and are among those who have faced many investigations for alleged siphoning of 45 billion rupees ($541 million) from Religare. The brothers, who deny wrongdoing, are currently on bail after being jailed earlier.

After new management conducted internal probes starting 2018, Religare filed various complaints to investigate alleged wrongdoings and recover funds.

In an Oct. 6 letter to Delhi police, Religare called for a "fair & proper investigation" into past financial dealings and said some of the complaints it filed during 2019-2023 had not been looked into.

"Any unlawful loss caused to its (Religare) subsidiaries affects REL's public shareholders," its Vice President Legal, Manpreet Singh Suri, wrote in the letter, which has not been made public but has been reviewed by Reuters.

Asked about the letter, Religare said in a statement its management "will continue pursuing all the legal actions rigorously".

A representative of the Burman family, Mohit Burman, said "we would like to see the company (Religare) use all legal remedies to recover any funds that are due."

The Delhi police and the Singh brothers did not immediately respond to Reuters queries.

Religare provides loans to small and mid-sized businesses and also has health insurance and broking services units.

A takeover by the Burmans would pit the billionaire family against other prominent names in the same business, including tycoon Mukesh Ambani's Jio Financial Services.

(Reporting by Aditya Kalra and Arpan Chaturvedi; Editing by Kim Coghill)

By Arpan Chaturvedi and Aditya Kalra