Online retailer Coupang said all the customer information leaked from the South Korean company has been deleted by the suspect, according to an emailed statement on Thursday.

The company said a former employee downloaded personal information of about 3,000 of Coupang's 33 million customers, which the person deleted without transferring to a third party.

Coupang said it had identified a former employee but did not disclose details about the alleged suspect. The company added that the individual had confessed to details related to the incident.

South Korea's science ministry said in a statement on Thursday that the incident remains under investigation and that the allegations raised by Coupang have not been confirmed by authorities.

The ministry, which is leading a joint investigation team with private-sector experts into the data breach, said it sent a strong complaint to Coupang about the firm's "unilateral disclosure" of allegations while the investigation is ongoing.

Earlier this month, South Korea's President Lee Jae Myung called for tougher penalties on the U.S.-listed company for corporate negligence in one of the country's worst data breaches.

-Heejin Kim/Reuters