The Indian subsidiary of online deals giant Groupon has accidentally published email addresses and passwords of its 300,000-strong subscriber database, reports and the company said.

Daniel Grzelak, founder of the Internet security website shouldichangemypassword.com, found the security breach of sosasta.com while running a Google search for publicly available databases.

Sosasta.com, an online discount portal acquired by Groupon in January 2011, alerted its subscribers Tuesday and posted a message on its Facebook page asking users to "change your Sosasta password immediately", says an AFP report.

"Over this weekend, we have been alerted to a security issue potentially affecting subscribers of Sosasta. We wanted to let you know that the issue has been brought under control and your accounts are secure," the message said.

Grzelak's website shouldichangemypassword.com holds a database of 1.3 million compromised email addresses, allowing users to check if their own email address is among those deemed unsafe, says the report.

Groupon said it would review Sosasta's security procedures and put in place "measures designed to prevent this kind of issue from recurring," AFP reported.

"Groupon takes security and privacy very seriously. Our users' trust is of paramount importance to us and we deeply regret this incident," it quoted the firm as saying. "This issue does not affect data from any other country or region."