Onslow County Manager David Cotton resigned Wednesday and gave few details on his sudden departure after two years in the manager’s position. Cotton turned in his resignation during a closed session at the special meeting of the Onslow County Board of Commissioners held Wednesday morning. Board Chairman Jack Bright said the resignation was effective immediately and Cotton only indicated that it was to pursue other career opportunities. Bright said after returning to open session the board appointed Sharon Russell, who currently serves as the deputy county manager, to serve as interim county manager.