The opposition believes that NAB's case is weak and the bureau is just using tactics for arm-twisting of the Pakistan Muslim League-Nawaz leaders by implicating them in the MMBP case.
The MMBP was launched in June 2015 and the bus service was inaugurated by the then chief minister of Punjab, Shahbaz Sharif, in Jan 2017.
Six top-ranking national and international firms had taken part in the execution of the MMBP. They completed the project two years ago and almost all of them are presently engaged in other national projects.
A source told Dawn that the heads of six firms, who worked on different segments of the MMBP, had obtained pre-arrest bail from court, but the head of another company, who could not get bail, had been arrested by NAB.
The said inquiry was split into two investigations as per transactions of offences committed in the MMBP
In December, 2017, NAB chief had ordered investigation into the alleged corruption in MMBP
after a Senate panel had decided to expand the scope of its investigation into alleged corruption of $17.5 million in MMBP
and the transfer of money abroad, as fresh details revealed a link between a top official of China-based Yabaite Technshyoshylogy Company Limited and the Yabaite Pakistan Construction Group Private Limited.
The investigation into the alleged corruption in the MMBP
was initiated in December 2017 on the direction of the NAB chairman after the Senate Standing Committee on Finance forwarded the case to it.
According to media reports last year, Capital Construction and Engineering Ltd, a subcontractor of the MMBP, had been involved in laundering money along with Chinese company Jiangsu Yabaite Technology.
Allegedly, during the investigation, the Chinese company had claimed that it had received the money through Capital Construction and Engineering Ltd for the MMBP.
The Yabaite-Pakistan is among three companies working on the Rs17.6bn ($167m) MMBP. The China-based Yabaite Technology is also facing a probe by the China Securities RegulaAtory Commission (CSRC) over alleged violation of Chinese securities laws.
The NAB has already approached the Federal Investigation Agency (FIA) to ask for complete records of the MMBP after initiating a probe.
The police had arrested the suspects after registering a first information report against them for fraud in connection with the MMBP.