The CBI is fully convinced that the Rs 90 lakh seized from Railways Minister Pawan Kumar Bansals nephew Vijay Singla on May 3 was in fact meant for the minister. Investigators are likely to question Bansal in the days to come,several senior officers said. We have incontrovertible evidence that the bribe amount was meant for the minister, a top CBI source in Delhi told The Indian Express on Monday. The buck has to stop somewhere. And in this case,it cant stop at a mere businessman. The source added that investigators have enough evidence to tie up the money trail. The fact that the bribe cash came from a company involved in railway projects,and that it was seized from a businessman who happens to be the ministers nephew was the starting point in establishing a quid pro quo,sources in the CBI said. Investigators are learnt to be building their case on call detail records and transcripts of conversations between major players in the story. These details,checked against actual events as they occurred,clearly reveal the larger picture,sources said. Preliminary investigations suggest that Mahesh Kumar,who was appointed Member Staff in the Railway Board on May 1 but who was eyeing the more lucrative post of Member Electrical,requested Sandeep Goyal to ensure that he (Kumar) be given additional charge of General Manager,Western Railway and Signals and Telecommunication,until he became Member Electrical,CBI sources said. Goyal,whose company M/s Pyramid Electronics in Panchkula is believed to manufacture electrical components for the Railways,allegedly demanded Rs 2 crore to do the job,the sources said. Mahesh Kumar allegedly tapped Narayan Rao Manjunath,managing director of Bangalore-based M/s GG Tronics India Pvt Ltd,which builds,supplies and instals electronic safety systems for the Railways. According to sources in the CBI,Kumar in return promised Manjunath official favours once he became Member Electrical. Manjunath was able to raise Rs 90 lakh initially,which,according to investigators,was arranged to be delivered at Chandigarh with the help of three other accused,Rahul Yadav,Samir Sandhir and Sushil Daga. It was understood that the remaining Rs 1.1 crore would be arranged after 3-4 days,the sources said. Bansal has said he has no knowledge or proof about the matter. Though a close relative,he (Singla) or any other relative of mine does not and cannot meddle in my official function or influence my decision.There is also no business relationship between his and my family, the minister said in a statement issued on May 4. He said he was looking forward to an expeditious investigation by the CBI.