David Clarke submitted his resignation as Milwaukee County sheriff on Thursday afternoon, The Daily Caller is told.

It is not yet clear why Clarke decided to resign. Reached by phone, Milwaukee County clerk George Christenson confirmed the resignation but said that Clarke provided no details about why he is quitting mid-term.

WISN radio host Mark Belling first reported Clarke’s resignation.

Clarke was in the middle of his fourth term in office. He was first appointed sheriff in 2002 and won election that same year. He won re-election most recently in 2014 and would have been up for another run next year.

Clarke was recently in the running for a high-level position at the Department of Homeland Security. He announced in May that he was under consideration for the job, but he pulled his name from consideration the next month.

A frequent Fox News contributor, Clarke has been a staunch supporter of President Trump’s tough-on-crime and tough-on-immigration positions.

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