DNA: Kolkata Rape case -- 5000 people attacked hospital to destroy evidence?

The nation was angry after the rape and then murder of a doctor in Kolkata. Seeing the anger, the High Court took a big decision and handed over the investigation of the case to CBI. But someone is very upset with this decision of the court and perhaps this is the reason why 5000 goons attacked the hospital at midnight. This attack is now being linked with evidence. It is believed that the mob had come to destroy evidence.