In a move that could further vitiate Centre-state relations, the Anti-Corruption Branch (ACB) of the Delhi government on Monday registered an FIR in the alleged Rs 400-crore tanker scam against the previous Sheila Dikshit government as well as the current Kejriwal dispensation. ACB chief Mukesh Meena said both the CM and his predecessor may be called for questioning.Meena said the FIR was registered under the Prevention of Corruption Act, along with two other sections. TOI has learned that Section 13 (1D), on misuse of power, and sections 120B and 409, which refer to hatching of a criminal conspiracy and criminal breach of trust by a public servant, have also been invoked. The FIR (No.10) is based on the report of an inquiry by the AAP government and forwarded to ACB by the LG and a complaint by BJP's Vijender Gupta demanding a probe against Kejriwal too for not scrapping the contract. The case dates back to 2012 when Delhi JalBoard, with Dikshit as chairperson, had awarded tenders for hiring 385 stainless steel water tankers from private companies. On June 19 last year, the AAP government set up a fact-finding committee on the deal which, in its report submitted in August, alleged a scam of Rs 400 crore.The committee found that a consultant had been appointed on a nomination basis, causing a loss of Rs 36.5 crore. Though the tender of one company was rejected on the ground that it was the only tender, later work was awarded on a single tender.The committee calculated the loss on account of awarding of work at higher rates compared to the rates quoted by another firm at Rs 323.9 crore. After the report was submitted, Mishra wrote to the CM, asking for an FIR to be lodged against those involved in the scam. On June 16, the LG forwarded the report to the ACB for appropriate action, after Gupta, MLA and the leader of the opposition in the assembly , wrote to him a day earlier.The FIR first quotes the fact-finding committee and endorses its findings. Subsequently, it mentions the Kejriwal government, saying that “the allegations of irregularities are grave in nature and involve public money. Prima facie, an offence is made out against both parties", according to a source.Gupta said in his complaint to the LG that Kejriwal and Mishra were equally guilty as they didn't take any action for almost 10 months.“The AAP government slept over the key findings of the WTDMS (Water Tankers Distribution Management System) committee report that the appointment of the consultants was done in an arbitrary manner on a nomination basis, contravening the Central Vigilance Commission and Comptroller and Auditor General (CAG) guidelines,“ Gupta wrote. “The previous govern ment awarded the work to some firms by accepting a single tender and awarded them zones of their own choice whereas the bid of a company was rejected on the ground of a single tender.Moreover, change of NIT (notice inviting tenders) conditions was carried out to extend an undue favour to contractors, ignoring government revenue,“ he said.On Friday, Mishra had demanded Dikshit's arrest.Claiming credit for the probe into the scam, Mishra had told TOI, "Gupta only sent a one-page complaint to the LG on the issue. Our government formed a fact-finding committee for a detailed inquiry into the scam which clearly indicts Dikshit for allowing irregularities in the tendering process, leading to a loss to the public exchequer of about Rs 400 crore.“ When asked, why the AAP government did not cancel the tanker contract, Mishra had claimed that it would have affected water supply in the city