The data of around 420,000 Hong Kong customers of Louis Vuitton were leaked from a breach, the city's privacy watchdog confirmed on Saturday.

The Office of the Privacy Commissioner for Personal Data (PCPD) said while the data breach took place in June, it was only notified on Thursday, more than two weeks after the French luxury fashion house's SAR office was made aware of the incident.

"An investigation has been launched against LVHK (Louis Vuitton Hong Kong) in accordance with established procedures, including whether there was delayed reporting of the incident," the PCPD said in a statement.

No complaints or enquiries were received so far, it added.

The office said the data leaked included customers' names, passport numbers, dates of birth, addresses, email addresses phone numbers, transaction records and product preferences.

The breach was first detected by Louis Vuitton's global headquarters on June 13. LVHK was then notified of the incident on July 2.

The PCPD urged companies to report data breaches as soon as possible, so remedial measures can be taken to minimise the damage to affected parties.