Asos has now informed its customers that hackers are in possession of detailed profiles belonging to potentially millions of users of the online store. This update arrived only after BBC News politely informed the retailer that cyber criminals had reached out to say this week's breach went somewhat beyond the "basic contact details" Asos had previously suggested might have been accessed.

So, to be clear: names, addresses, phone numbers, emails and customer numbers are now in the hands of cyber criminals. As are the searches customers have made on the website. Terms like "reclaimed vintage", "glamorous wide fit" and "Asos petite" are visible in the data. Yes, your late-night browsing history is now someone's phishing ammunition.

With this information, scammers may be able to craft potent phishing attack emails or phone calls. The risk to individuals is now higher, and customers are being warned about potential impersonation scams.

In its email to customers, Asos confirmed data profiles were taken but said no bank details or passwords were accessed. "Please remain cautious of unexpected messages or calls claiming to be from Asos," it said. "We will never ask you to share passwords, security codes or payment details through an unsolicited message or call." The company did not respond to questions about the scale of the breach, which is one way to handle things.

The high profile hack made global headlines on Tuesday when cyber criminals used Asos's own app system to send a pop up notification to potentially millions of people. Later that day the firm confirmed to shareholders via the London Stock Exchange that the pop up was sent by an "unauthorised third party" and "basic personal information including name and contact details may have been accessed." The company then sent an email to customers with similar wording.

On Wednesday evening the cyber criminals responsible contacted the BBC sharing a sample of the stolen data which showed the true extent of the hack. The BBC held off publishing this article to allow Asos to contact its customers first, which is more courtesy than the hackers showed.

Asos said it is still investigating how the hack happened. It told customers hackers "gained access to an Asos employee account by impersonating a trusted contact to obtain log in credentials." With that log in to an unnamed service, the hackers were able to download the customer data.

In the pop up notification sent to customers by the hackers, they claimed they had "compromised the Snowflake instance". Snowflake is a popular data storage and analysis company whose customers have been breached in the past due to unauthorised log ins. The cyber criminals, calling themselves Xuanyewen, claimed to the BBC they used a platform which is built natively on top of Snowflake - called Simon AI - to gain access to the data. Simon AI has been contacted for comment. Snowflake previously said its platform had not been breached.

Asos said customers are not being asked to take any action. But cyber security experts have warned users to change passwords as a precaution and be on alert for suspicious activity.

Asos said its website and app are safe to use and "we know our customers trust us with their information". "We take that responsibility seriously and have already taken additional steps to further strengthen security controls," it said. Which is reassuring, if slightly belated.