Back in May, the Internal Revenue Service said thieves nabbed info for 100,000 people through its transcript website. Today the agency increased that number by an additional 200,000 folks, bringing the total number of potential cases to 334,000. Using a "Get Transcript" tool to access tax returns from previous years -- a vulnerability that the government knew about -- hackers were able to use personal details on 610,000 taxpayers to retrieve tax-related info on the over 300,000 accounts. Most likely, the culprits were looking to eventually claim refunds with the stolen goods. The IRS says it's "moving aggressively" to keep those who are affected or potentially at risk safe, and it's sending out letters to inform individuals if their information was accessed. This isn't the only tax-related incident facing the US government this year either, as 800,000 people received bad tax info through Healthcare.gov in February.

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