How Banks Detect and Flag Mule Accounts

Why banks monitor transactions

Every bank in Malaysia must, by law, monitor the transactions that pass through its accounts. This duty comes from AMLA and Bank Negara Malaysia’s rules.

Banks monitor for two reasons. First, to find transactions that may be linked to money laundering, terrorism financing or other crime. Second, to avoid penalties from the regulator for failing to spot and report suspicious activity.

Knowing how this works helps you see why your account may have been flagged, even if your transactions were genuine. A flag starts a process. It is not a finding that you did anything wrong.

AMLA Section 14: the duty to report

AMLA Section 14 requires every financial institution to report suspicious transactions to Bank Negara Malaysia. ^[f1] All bank monitoring in Malaysia rests on this duty.

A bank files a suspicious transaction report (STR) when its systems or compliance staff see activity that could be linked to an unlawful purpose. The bank does not need to confirm that a crime happened. Suspicion is enough.

After an STR is filed, Bank Negara may pass the information to PDRM or other enforcement agencies. This can lead to an account freeze or an investigation.

Bank Negara’s monitoring rules

Bank Negara Malaysia issues detailed rules that tell banks what to look for and how to respond. ^[f2] They cover checking who customers are, the limits that set off monitoring, and how to report.

Banks must run systems that can spot unusual patterns in every type of account. The rules are updated from time to time to keep up with new methods used by criminal networks.

Following these rules is compulsory, and banks that fall short face action from the regulator. So a bank may err on the side of caution, even when that catches innocent account holders.

The Semak Mule platform

Semak Mule is PDRM’s website where anyone can check whether a bank account number has been reported for mule account activity. ^[f3] Banks, businesses and members of the public all use it.

When a scam victim makes a police report naming the account that received their money, that account number goes into the Semak Mule database. The account holder may not know their account is listed.

Over 190,000 accounts have been flagged through enforcement work. ^[f6] If your account is on Semak Mule, a police report has linked it to a complaint. This can lead to account freezes and investigations.

Transaction patterns that trigger alerts

Bank systems watch for patterns that differ from how an account is normally used. ^[f4] Knowing them helps you see what may have flagged your account.

Quick transfers in and out. If money arrives and is sent on to another account within minutes or hours, the system treats it as a possible pass-through.

Sudden large deposits. If your account usually handles small amounts and a large sum appears, the compliance team will look into where it came from.

A dormant account waking up. An account unused for months that suddenly starts moving money gets closer checks.

Many recipients. One account sending money to many different accounts in a short time is a pattern linked to spreading scam money.

How AI and machine learning screen accounts

Malaysian banks use artificial intelligence and machine learning to watch transactions as they happen. ^[f5] These systems go beyond simple rules and can spot complex patterns a person might miss.

The models learn what normal looks like for each account from its history. When a transaction does not fit, the system raises an alert for the compliance team.

They can find links between accounts, detect layering (moving money through several accounts to hide where it came from), and flag activity coordinated across accounts held by different people.

What happens after an account is flagged

When the system flags your account, the alert goes to the bank’s compliance team, and a person reviews it.

The compliance officer looks at the flagged transactions, your account history and what is known about the people involved. If the officer decides the activity is genuinely suspicious, they file an STR with Bank Negara Malaysia.

Depending on how serious it looks, the bank may restrict your account at once, ask you to explain, or both. Sometimes the bank shares information directly with PDRM, which can lead to a freeze under CPC Section 116D.

How much enforcement there is

Over 190,000 accounts have been flagged. ^[f6] That shows how actively Malaysia acts against mule accounts.

The National Scam Response Centre (NSRC) hotline 997 allows fast reporting. After a report, funds can be traced and frozen very quickly, sometimes within hours. This protects victims, but it also means an account can be frozen before the holder knows why.

Innocent account holders can be caught. An account that received one payment from a scam victim’s money can be frozen alongside accounts used deliberately for crime.

What this means if you did nothing wrong

A flag means the bank’s systems or a police report linked your account to suspicious activity. It does not mean you are guilty of an offence.

What happens next depends on how you respond, the evidence you give and the legal steps you take. Working with the investigation and keeping clear records of your transactions can help settle it.

If your bank has told you about a restriction, or the police have contacted you about a mule account investigation, a lawyer can explain the likely trigger and help you answer correctly. Our guide on what to do when your account is frozen covers the first steps.

Sources

1. Anti-Money Laundering, Anti-Terrorism Financing and Proceeds of Unlawful Activities Act 2001 (AMLA), Section 14
2. Bank Negara Malaysia, Anti-Money Laundering and Counter Financing of Terrorism Policy
3. Low & Partners, “Keldai Accounts: When Helping a Friend Becomes a Criminal Offence” (2024)
4. Raj, Ong & Yudistra, “Unveiling the Mystery: When Your Bank Account Gets Frozen by the Law” (2024)
5. PDRM, Semak Mule Platform