PHILADELPHIA (CBS) – The breach of taxpayers’ data is much worse than the IRS previously thought.

A Treasury Department investigation reveals the number of people caught up in last year’s cybertheft is roughly 720,000.

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The IRS will warn affected taxpayers about potential identity theft and offer them free credit protection.

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They will also get an additional personal identification number to protect future tax filings.

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The IRS has disabled the online tool used to steal personal information.