Ccontact the IRS Identity Protection Specialized Unit at 1-800-908-4490 to report the identity theft. Your son (and you if he is a minor) will also need to fill out the IRS Identity Theft Affidavit, Form 14039. See attached link.
You should also notify the credit bureaus in case the thief has opened accounts in his name and with his SS #.
Contact a tax specialist to help get back money that the IRS "took" for taxes on wages that your son did not earn, and thus did not owe taxes on.
A police report should also be filed by you (or your son if he is over 18) with the local police where you live. See attached link for more information and forms.
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