Terming as "very serious" reports alleging that ISRO benefited a private firm through allocation of scarce S-band spectrum without a bidding process, Left parties today demanded a thorough probe into the "new scam".

"This is a new issue. The ISRO is under the Department of Space which is under Prime Minister (Manmohan Singh). This is also a new scam," CPI(M) Politburo member Sitaram Yechury told reporters here.

CPI National Secretary D Raja said the new revelations were "very serious", a view echoed by senior RSP leader Abani Roy who demanded a JPC into the matter.

Media reports claimed that the Comptroller and Auditor General has initiated inquiries into ISRO's agreement with a Bangalore-based firm for launch of two satellites besides allegedly providing 70 MHz of S-band spectrum for a period of 20 years without going through a bidding process.