CBI on Monday received a fresh tranche of files and documents from the Coal Ministry and began examining them as part of its probe in coal block allocation scam.
CBI sources said the fresh set of documents came late in the evening and the scrutiny has started.
They said only after analysing the documents, they would be able to ascertain the number of files which have still not been provided.
Nearly 150 files and documents were to be received by CBI from the Coal Ministry.
Coal blocks scam: CBI wants files, but ministry has only pointed replies
Earlier in the day, a Coal Ministry official said a report, along with the documents and files, was despatched to CBI.
Coal Minister Sriprakash Jaiswal did not make any comment on whether the files have been dispatched but said "the instructions of the Supreme Court are being followed."
Asked about details of the report the ministry has sent to CBI, the official declined to disclose the contents citing confidentiality.
While hearing the case on August 29, the Supreme Court had directed CBI to give a list of documents, files and information sought by it within five days to the Coal Ministry which, in turn, was to furnish them within two weeks.
Asked when the ministry will file a complaint with regard to the missing files, the official said "we will take action in accordance with the directions of the Supreme Court and as per the law and within the timeline which has been prescribed for us."