Indonesia’s largest e-commerce platform, Tokopedia said, it is investigating an attempted cyber attack and claims that details of millions of its users had been leaked online.

“We found that there had been an attempt to steal data from Tokopedia users,” said Tokopedia’s spokesman. “However, Tokopedia ensures that crucial information such as passwords remains successfully protected behind encryption.”

“At this moment, we continue to investigate further into this matter and there is no additional information that we can share”.

In Saturday, Under the Breach, a data breach monitoring firm had published a screenshot on Twitter from an unnamed individual who claimed he had acquired the personal details of 15 million Tokopedia users during a March 2020 hack on the e-commerce site.

The screenshot contains details including names, emails and birthdays of Tokopedia’s users. The hacker alleges he or she is in possession of a much bigger user database and asks for assistance to “crack” users’ passwords.

According to Under the Breach’s report, on Sunday, the hacker had updated the post to offer the details of 91 million Tokopedia users for “$5,000 on the Darknet”.

Tokopedia is backed by $2 billion in funding from investors including SoftBank Group Corp’s Vision Fund as well as Alibaba.Tokopedia’s founder and CEO William Tanuwijaya is one of Indonesia’s most prominent tech entrepreneurs. Tokopedia claims to have more than 90 million monthly active users.