I need a legal/professional advice on a case from Nairalanders

A cash in a friend bank account was withheld by bank.

He got to know about this when he decide to made some transaction via his mobile banking app while his account balance showing minus/negative

His lawyer wrote a several letters to the bank about the incident which the bank ignored

His lawyer decide to sued the bank,then bank came with police/court order that was used to withheld the cash.

Which stated that my friend obtained money under false pretence,which my friend didn't understand. That they (police) have been looking/searching for my friend where about.

The judge adjourned the case and instructed my friend lawyer to write an invitation letter to police,to bring whoever that complained about my friend account to the court

The question is this,did police has right to arrest my friend on,before or after the case? Now that the case is in court of law...

Thank you...

Your friend committed fraud Oga or his account was used to commit Fraudulent activities.