Wyoming's U.S. Attorney Matthew Mead has announced his resignation, effective tonight at midnight, according to a press release from his office.

Mead, a Jackson native, has served as the state's U.S. attorney since 2001. He has been mentioned as a potential candidate for Wyoming's vacant U.S. Senate seat, and on Tuesday said he would wait until next week to make a decision about his candidacy for that position.

The release said Mead will return to his family ranching operation in Jackson.

Mead recently learned that he was on a list of federal prosecutors that Justice Department officials considered firing last year. It remains unclear why Mead was on the list. He told the Star-Tribune in late May that he was "surprised" to learn his name was on the list.

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