Kolkata, Sep 19 : The Calcutta High Court on Tuesday cautioned the Central Bureau of Investigation (CBI) of sending reports to the Prime Minister's Office (PMO) against some of its officials engaged in the investigation into the multi-crore cash for school jobs case in West Bengal. As the CBI counsel submitted a report on the optical marks recognition (OMR) sheets to the single-judge bench of Justice Abhijit Gangopadhyay, the court expressed doubts over a section of the central agency officials diluting the investigation. 'It seems that there is an attempt to cover up the culprits. Will I have to send a report to the PMO that CBI is unable to do anything? The CBI officers are not kids. They know how to proceed,' Justice Gangopadhyay observed. He was also heard telling deputy solicitor general Billwadal Bhattacharyya, representing the CBI, that in the past the central agency officials had been cautioned, and time has come to report the matter to the PMO. 'Not all in the CBI, but some within the agency are trying to shield the culprits,' Justice Gangopadhyay noted. He also observed that during the course of questioning, CBI officials skipped a number of important questions, adding that he might question the CBI director as to why such questions were excluded. He also asked whether the statement of Trinamool Congress MLA Manik Bhattacharya, the former President of West Bengal Board of Primary Education (WBBPE), has been recorded. The CBI counsel said that already the agency has made substantiating progress in the case and it needs some more time to wind up the probe. /IANS