Three partners of a private firm were booked for allegedly duping the Kalyan Dombivali Municipal Corporation of Rs 20.69 crore in a utility project being built under the state-funded Basic Services to Urban Poor (BSUP) scheme, an official said on Saturday.

The firm did not complete the work in time, entered into illegal third-party agreements, defaulted on payments to the civic body and also brought about litigation to stall the project, a KDMC engineer said.