I would like to answer this remark from Mr. Kamal!
During an investigation, police and rangers (whoever is investigating) arrests people who they find involved in the crime. Those criminals are the sources of their bosses. But those criminals can't be used in the court as evidences.
All the information that comes out of those criminals is stored in form of reports. Those reports give an idea about who is the source of crime out there.
The documents that Zulfiqar Mirza has, are reports based on such criminals' information. They can't be used in the court to punish a criminal but they are TRUE nonetheless.
Mr. Kamal should not try to fool people with such remarks!