Elon Musk caused alarm among federal employees and drew ire over an email sent on Saturday requesting that employees summarize their work for the week, and warning on social media that a failure to do so would be taken as a resignation.

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A defiant threat by Elon Musk warning that federal employees will be given "a second chance" to respond to his email asking them to justify their jobs or risk termination is likely to spark another round of confusion across the U.