The sources said the bonds had been purchased from the Perpetual Treasuries which company is now embroiled in a controversy.
They said details about the losses had been already reported to the CB and it had launched an inquiry.
The CB had asked for a committee consisting of outsiders for the probe as some CB employees were also to be investigated.
The sources said a CB official accused of committing irregularities had submitted his resignation on hearing about the proposed investigation, but the CB hierarchy had not accepted his resignation in view of the investigation.
(by Shyam Nuwan Ganewatte - island.lk)