A six-member inquiry team of the anti-money laundering department of the central bank went to the Dilkusha, Motijheel and Mohakhali branches of the private bank for probing the matter.

The BB earlier received an SEC letter, which mentioned that around 15,000 beneficiary owners' (BO) accounts were opened by the depository participant (DP) of the Premier Bank using a single address.

About 5,500 BO accounts did not have any address while another 3,000 accounts were opened using only one address, the SEC letter mentioned referring to its preliminary findings.

As it is mandatory to mention a bank account number and the branch while opening a BO account, there are possibilities that massive irregularities might have taken place in opening a huge number of bank accounts with the Premier Bank, which is an act of money laundering.

According to sources, the BB has a guideline -- 'know your customer' -- that clearly says what to do in opening the bank accounts. Non-compliance of the guideline is considered as violation of the Anti-money Laundering Act.

The BB inquiry team is focusing on irregularity, if any, in opening a huge number of bank accounts, they said.

The team will submit its preliminary report within a couple of days. "The central bank would take action against Premier Bank if there is any irregularity in opening these bank accounts," said a source.

The central bank will form more teams to probe the first such scam in the country. They will visit all the branches of the private bank in phases.

However, a branch manager of the Premier Bank said the chairman of the board of directors put pressure on the managers of different branches to open a huge number of accounts. The managing director was also involved in it.

"The branch managers can explain if they are asked," he added.

The SEC on Saturday suspended a Tk 55 crore public floating of Premier Bank after around 25,000 'fake' BO accounts were found in a preliminary investigation by the capital market watchdog.