Coupang staff obstructed a South Korean government probe into a massive breach of customer data by deleting sensitive information, the ministry carrying out the investigation said, adding the country’s largest e-commerce firm defied an order to preserve access logs and other data.

South Korea’s Ministry of Science and ICT said in a report published on Tuesday that the breach exposed private data of nearly 34 million customers, rejecting Coupang’s claim that the amount of people affected was far smaller.

The report, which was the result of a joint public-private investigation, said the intruder was a former staff engineer who had compromised personal data including names, phone numbers, addresses and building access codes.

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The incident has boiled over into a geopolitical spat between the US and South Korea, with Vice-President JD Vance casting Korea’s crackdown on Coupang Inc, which is listed in New York but does business mostly in Korea, as an assault on America’s tech industry. President Donald Trump has also threatened 25 percent tariffs on the country.

The report offered fresh details about the breach, including claims by the intruder that customers in Japan and Taiwan region were affected. It also included English correspondence between the intruder and Coupang officials, which read: “due to a not-so-hard-to-find vulnerability in Coupang’s system, billions of user privacy data items are at significant risk of leak.”

The former engineer exposed 25.6 terabytes of data and accessed the Coupang system between April and November, according to the report. The intruder had tested the same vulnerability as early as January last year, it said.

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The science ministry is just one of several groups probing the data breach. It said South Korea’s Personal Information Protection Commission would follow up with more details on the leaked data. The Korean National Policy Agency is also conducting an investigation, while other relevant ministries are also reviewing issues within their respective jurisdictions, the ministry said.

Coupang has said the probe which has included office raids, punitive actions from at least 11 South Korean government agencies and criminal charges lobbed against company executives, some of whom are US citizens, is unfair. Coupang’s lobbying efforts in Washington, which have cost the company at least $5.5 million in the last two years, have helped and have mobilized US officials to rally on the company’s behalf.