The security minister told lawmakers the alert was not disseminated to banks because it had been prepared initially by a non-government organisation and that “reservations” had arisen about certain “unverifiable information” contained in it.

Earlier this month, anti-human trafficking campaigners expressed shock at news of the suppressed alert. That coincided with the publication of a report by the city’s Ombudsman finding a complaint that police were unreasonably withholding data on dirty money transactions linked to human trafficking to be “unsubstantiated”.

The 24-page alert, titled “Combating Human Trafficking in Hong Kong and the Asia-Pacific Region”, was prepared by the recently formed Fraud and Money Laundering Intelligence Taskforce. It was designed to sharpen the ability of financial institutions to spot and report suspicious transactions linked to the illicit trade of people.

Set up in May last year, the task force is a police-led joint effort involving the Monetary Authority and major banks and financial institutions locally. A review is under way to determine whether it should become a permanent feature of the city’s anti-money-laundering apparatus.

Hong Kong and China are members of the Financial Action Task Force (FATF), a watchdog that sets international standards on combating money laundering and has ranked the trafficking of people into commercial exploitation as one of its core concerns.

The Paris-based group says human trafficking is a global crime racket earning profits of about US$150 billion (HK$1.17 trillion) a year – the third-largest source of funds for organised crime after illicit drugs and arms.

The task force had sent representatives to the city to evaluate how well local authorities were upholding obligations as a long-standing FATF member.

An evaluation team from the watchdog will produce a report assessing Hong Kong’s implementation of anti-money laundering and counterterrorist financing standards.

In the two-hour meeting, FATF representatives asked Chan what policies had been adopted locally to fight money laundering.

Also attending were senior staff from the Securities and Futures Commission, the Monetary Authority, and the Financial Services and the Treasury Bureau as well as Clement Cheung Wan-ching, CEO of the Insurance Authority.

The FATF will next visit officers at various financial institutions in the city.

A bureau spokesman said Hong Kong was committed to putting in place robust measures to combat money laundering and terrorist financing.

“Our law enforcement agencies are fully committed to fostering closer cooperation with other jurisdictions to combat cross-border money laundering and terrorist financing activities and will continue to work closely with their global counterparts to this end,” he said.

Neither police nor the Monetary Authority could be reached for comment.