Police's Gulshan zone Assistant Commissioner Nurul Alam said a case has been filed over the incident.
"RAB has arrested them on charges of demanding Tk 100,000 from a man named Shahjahan Shamsu. One Abu Zafar filed a case on behalf of Shamsu," he told bdnews24.com.
Those who have been nabbed are Bhatara police's assistant sub-inspectors (ASI) Mir Sirzaul Islam and Kawser Ahmed, constable Abdur Rahman, Asaduzzaman and a female, 'Borsha'.
According to the case details, they had trapped Shamsu by using Barsha and demanded the money to let him go.
An official of Dhaka Metropolitan Police told bdnews24.com that Shamsu was arrested for allegedly committing adultery in a house at Bhatara area on Friday night.
"A deal was made and the policemen agreed to let him go in exchange of Tk 100,000," he said preferring anonymity.
Shamsu's relatives informed the matter to RAB and the five, including the two ASIs were arrested from Kuril area on Saturday while the exchange of money was supposed to take place."