The IRS spokeswoman warns that all tax payments are due by April 15, even for people who find out they are theft victims after that date. (Often it can take 48 hours to get an e-filing receipt.) IRS computers won't accept electronic payments from e-filers whose returns are rejected because of theft, so last-minute e-filers who owe tax should consider printing a voucher and mailing it with a check.
WSJ: Tax Report: It's Tax ID-Theft Season