They include the Station Director (Commercial Broadcasting), Sadhana Bhatt and a husband-wife duo, Ashlesha and Mihir Mehta. The CBI said Ashlesha and Mihir work at AIR Ahmedabad as Transmission Executive and Production Executive respectively.

Bhatt and the Mehta couple have been accused of corruption, cheating, forgery and criminal conspiracy. Searches were conducted in the offices and residences of all the accused and investigations are underway.

According to the case details, the Ahmedabad station of AIR had broadcast 102 episodes of a programme titled Dungre Dungre Vikas Na Vyara in 2006-07. Acting on a tip-off about alleged corruption in the production and broadcast of this series by the AIR employees, the CBI started a probe into the case.

During investigation, the CBI sleuths found that the Mehta couple had approached the Tribal Welfare Department (TWD) in 2006 to express AIR's willingness to air a series for the department. “When TWD agreed, the Mehtas recommended a private city-based production house, Manisha Creative Firm for producing the series. The 102 episode series was later broadcast and TWD paid AIR a sum of Rs 10 lakh for the production and broadcast of the series,” a CBI official said.

The probe further revealed that Manisha Creative Firm was a benami production house owned by the Mehta couple.

The couple has now been accused of criminal conspiracy, cheating and forgery and for making AIR suffer losses in lakhs. “Bhatt was very much hand in glove in the entire case,” a CBI official said.

Meanwhile, the CBI already has a strong case against Bhatt and has accused him of giving a clean-chit for the series despite the Mehta couple having lent their voice for the programmes.

“According to norms, no programmes with voiceover by an AIR employee should be broadcast by any AIR station. In fact, a certificate confirming the same is mandatory,” the CBI added.

Sources said the CBI was investigating the possibility of Manisha Creative Firm or any other private firm being involved in the production of other AIR programmes as well. Manisha Creative Firm is also under the scanner for its other sources of income.

Meanwhile, searches were still on till Thursday evening at the residences of the accused.