Some "anonymous" person had made the cassette available to him in Shimla and he also received an "anonymous" call and that caller said that he had some material to expose corruption, Mankotia told special judge B L Soni.
"The cassette was received by me as someone had left it in my house and after hearing the conversations, I found that the conversations were about financial transactions relating to elections", he told the court.
Mankotia said he had not made any audio-CD from the cassette in his possession and he had retained the original copy received by him and supplied the copy of the same to the police.
Virbhadra and his wife were booked by the state police on August 3, 2008 under the Prevention of Corruption Act for alleged misuse of official position and criminal misconduct when he was chief minister in 1989.
According to police, they were booked on the basis of the cassette released by Mankotia in 2007.
The cassete purportedly contained telephonic conversations regarding monetary transactions between Virbhadra Singh and Mohender Lal who is now dead. (MORE)