What is Suspicious Transaction Report (STR) and Suspicious Activity Report (SAR)?

Describe the STR/SAR identification and reporting procedure.

An account of your customer has been credited by cash 7 (seven) lac taka and debited by cash 5 (five) lac taka in a day. Will these transaction be considered for Cash Transaction Reporting (CTR) or not? Explain.

Mention the some indicators/red flags for identification of STR.