The police are struggling to file a supplementary charge sheet against the people arrested in connection with the CSMT foot overbridge collapse earlier this year as they still await the Brihanmumbai Municipal Corporation's (BMC) permission.

"As per section 197 of CrPC, it is imperative to seek permission from the appointment authority before filing a charge sheet against government officer if s/he is involved in a crime related to discharging his/her duty," said a police officer.