Sen. Jeff Sessions, R-Ala., is demanding answers after a report surfaced that a U.S. Immigration and Customs Enforcement agent is facing punishment for arresting an illegal immigrant.

The unidentified agent could face a three-day suspension after he arrested a 35-year-old illegal immigrant from Mexico who had as many as 10 traffic violations.

The agent was ordered by supervisors to release the individual because he was not a "priority target." When the officer balked, he was threatened with a three-day suspension and the illegal alien was let go.

"The actions that it appears were taken by your agency send a message to agents in the field that they will be punished for doing their duty and enforcing the law," Sessions wrote in an letter to ICE Director John Morton and obtained exclusively by Fox News.

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