Here is some relevant information:
Decision/judgment of Supreme Court of India in case of in Ram Lal Narang Vs. State, Delhi Administration (AIR 1979 SC 1791), in that Hon’ble Court observed, at Para No: 21, as follows:
“21. Anyone acquainted with the day-to-day working of the criminal courts will be alive to the practical necessity of the police possessing the power to make ‘further investigation’ and submit a supplemental report. It is in the interests of both the prosecution and the defence that the police should have such power. It is easy to visualise a case where fresh material may come to light which would implicate persons not previously accused or absolve persons already accused. When it comes to the notice of the investigating agency that a person already accused of an offence has a good alibi, is it not the duty of that agency to investigate the genuineness of the plea of alibi and submit a report to the Magistrate? After all the investigating agency has greater resources at its command than a private individual. Similarly, where the involvement of persons who are not already accused comes to the notice of the investigating agency, the investigating agency cannot keep quiet and refuse to investigate the fresh information. It is their duty to investigate and submit a report to the Magistrate upon the involvement of the other persons. In either case, it is for the Magistrate to decide upon his future course of action depending upon the stage at which the case is before him. If he has already taken cognizance of the offence, but has not proceeded with the enquiry or trial, he may direct the issue of process to persons freshly discovered to be involved and deal with all the accused in a single enquiry or trial. If the case of which he has previously taken cognizance has already proceeded to some extent, he may take fresh cognizance of the offence disclosed against the newly involved accused and proceed with the case as a separate case. What action a Magistrate is to take in accordance with the provisions of the CrPC in such situations is a matter best left to the discretion of the Magistrate.” [Emphasis is added]
and also the Hon’ble Court held in the judgment that:
A ‘further investigation’ is not necessarily aimed at finding out materials against the accused. A ‘further Investigation’ may subserve the interest of the prosecution and, at times, even of the defence. There may be fresh materials, which may, on coming to light, necessitate ‘further investigation’ either for strengthening the case against the accused or for exonerating him.