The National Crime Agency (NCA) and other UK law enforcement bodies have applied to courts around the country in a co-ordinated operation to freeze 95 accounts containing an estimated £3.6m of suspicious funds.
The accounts are held mainly by Chinese students at UK universities, who appear to have been targeted by organised crime groups to launder the proceeds of crime. Such individuals are sometimes known as 'money mules,' because they often do not know what the third party is really using the account for, and may not know that operating a bank account in this manner is potentially illegal.
In one case, the police are seeking to freeze an account that now contains £25,000, although almost £150,000 passed through it in a 14-month period up to the end of 2018, City of London magistrates' court was told.
In another case, £44,500 in cash was deposited into an account between May and July 2018 even though the student account holder had told the bank she was expecting £12,000 a year from her parents to support her during her studies. Only £7,570 now remained in the account, the court heard.
International students are more at risk, especially where their home country applies controls and limits to personal foreign exchange transactions. Criminals will seek to circumvent those controls by taking advantage of legitimate routes for sending money overseas.
The vast majority of the accounts are with Barclays.
Since 31 January 2018, bank accounts with at least £1000 can be frozen on suspicion of unlawful activity by a magistrate in the absence of the account holder.
According to the NCA, the tell-tale signs that indicated the accounts were being used for money laundering included cash payments directly into accounts from so-called automated service devices, and small and frequent cash deposits to break up large transactions into smaller transactions below the reporting threshold ('structuring' or 'smurfing').
The accounts were identified by an unnamed through their anti-money laundering procedures. This bank, says the NCA, took a "ground-breaking stance to cooperate on a wholesale, evidential basis from the outset".