Pitamber Mahto was found hanging from a ceiling fan in his house in Press Enclave Colony in Vikas Nagar in West Delhi last Saturday, they said.
A suicide note has been recovered from Mahto in which he has allegedly accused his senior officials of trying to frame him in the theft which took place in the office on May 9 in which cash and gold worth around Rs 2.5 crore were stolen, police sources said.
Officials of the trade and taxes department had registered a complaint with the police and informed them about a carton missing from the tenth floor of the department's building adjacent to Delhi Police Headquarters containing 7 kg gold and Rs 10 lakh cash.
Police had registered a case at the IP Estate station and investigation was taken up.
Mahto's family, meanwhile, has approached Ranholla police station and sought a probe into the allegation made by him in his suicide note.