He was arrested after a detailed questioning regarding his business links, beneficiaries who were allegedly involved in bribery. Singh was grilled on various aspects of the case, projects handled by him and was confronted with related documents, sources said.
Singh was evasive during examination and could not explain some new evidence presented before him by the agency, they said.
He is facing two separate CBI cases - amassing disproportionate assets and high-level corruption in awarding contracts.
CBI Press Information Officer R K Gaur said Singh was arrested in an ongoing investigation in a case of alleged corruption.
Also Read
(Reopens DEL57)
CBI sources said the agency is probing alleged corruption in the laying of the underground cable contract worth Rs 92 crore in which rules and regulations were not followed by Singh, who was the Chief Engineer of Noida, Greater Noida and Yamuna Expressway, while awarding them.
The sources said it has emerged during the probe that the contract was signed in December 2011, but work had already been started by beneficiary companies in September that year and almost completed 60 per cent of the work when the contract was finally given.
The sources said another company NKG Infrastructure was allegedly given work of about 34.87 crore without any tender by Singh.
It is further alleged that Singh, as Chief Engineer, signed around 1,280 contracts amounting to Rs 950 crore in a span of eight days during November 2014.
Uttar Pradesh Police had also lodged a case against Singh but later filed a closure report.
"The allegations levelled in the FIR were that the then Chief Engineer...Entered into criminal conspiracy with unknown private persons/firms and awarded various contracts without following the laid down procedures and thereby caused undue pecuniary gains to the tune of crores of rupees to private firms and to himself.