Gupta said the scam involves senior Aam Aadmi Party (AAP) leaders and Indian Administrative Service (IAS) officers.
"It would, therefore, be appropriate in the interest of in-depth investigation that the multidisciplinary investigating agency CBI institutes an enquiry into the matter to reach to the depth of the scam and bring all the culprits to the book," Gupta told the media, adding the CBI Director had assured an investigation.
Gupta said he informed that CBI Director that the BJP delegation met Delhi Special Commissioner Police, Anti-Corruption Branch, on Tuesday and submitted a complaint on the scam.
"ACB took immediate cognizance and wrote to the Chief Secretary to seek permission to initiate a preliminary enquiry against the two officers Divisional Magistrate (Shahdara) Kuldeep Pakad and Divisional Commissioner Rajiv Verma. But a CBI investigation would take the probe to greater depth," he said.
"Pakad acted as kingpin in connivance with Transport Minister Kailash Gehlot and Divisional Commissioner Rajiv Verma," he added.
The Delhi government's Transport Department had directed the District Magistrate to provide 10,000 Civil Defence Volunteers to be deployed as marshals in DTC and cluster buses.
Only Delhi residents were eligible to be enrolled for these posts.
"However, senior Delhi government officers under the Office of Divisional Commissioner issued certificates to 400 people from Rajasthan, certifying them as Delhi residents, to help them get enrolled. It is reported that an amount of Rs 2 lakh was paid as bribe by each candidate for enrolment," Gupta said.
Lok Sabha MP from South Delhi, Ramesh Bidhuri, said that people suffering due to the oppressive policies of the then ruling Congress party, gave a massive mandate to AAP, which has been claiming to have eradicated corruption from Delhi.
"After coming to power, however, many cases of corruption by AAP leaders came to light one after another. They started speaking lies to the people every day and complained that the Central government does not allow them to work," Bidhuri added.
He said Chief Minister Arvind Kejriwal is trying to save himself by holding one officer responsible for corruption in the recruitment of marshals.
"How can such a big scam happen in the process of recruitment without the connivance of leaders and Ministers," he asked.
"If there is any morality left in Kejriwal, then first of all he should take responsibility for the corruption committed in this case, and besides apologising to the people of Delhi, should resign from the post of Chief Minister," he added.
( With inputs from IANS )