New Delhi, Sep 14 (IANS): The CBI Wednesday filed a case against the Delhi Development Authority (DDA) officials and a private firm for irregularities in the 2010 Commonwealth Games (CWG). Raids are also being made at 21 locations, including in Delhi and Mumbai, officials said.

"We have registered a new case in connection with the CWG regarding the construction of an indoor stadium for squash and badminton in the Siri Fort complex," a CBI official said.

A Special Investigation Team (SIT) of the CBI filed the case against the officials, including the DDA's retired chief engineer V.K. Panchal, the agency said.

According to the CBI, the accused also include a private contractor, B.E. Billimoria Co. Ltd.

"The estimated cost of construction was approximately Rs.118 crore but the contract was finally awarded at an approximate cost of Rs.154 crore, causing a loss of Rs.36 crore to the exchequer," said the official.

This is the first case registered by the Special Investigation Team (SIT) which was formed to study the Comptroller and Auditor General's report on the CWG preparations.

The raids are being conducted in the national capital region and other places.

"Raids are on in 21 locations - 16 in Delhi, two in Mumbai and one each in Noida, Sahibabad (Uttar Pradesh), and Gurgaon (Haryana)," the official said.

The Commonwealth Games in October last year were marred by charges of corruption, dubious contracts and poor execution of various projects.