Baltimore County Executive Johnny Olszewski announced Wednesday the second departure from his executive staff in recent weeks.

His chief of staff, Patrick Murray, is leaving in September. Murray has been chief of staff throughout Olszewski’s term. Olszewski has been in office more than three and a half years and is running for re-election in November.

Drew Vetter, Olszewski’s deputy administrative officer, resigned several weeks ago. Olszewski said at the time that leaving was Vetter’s decision.

Erica Palmisano, Olszewski’s press secretary, said Wednesday that Murray also was not asked to leave.

Olszewski, in a statement said, “Pat has been an invaluable partner and played an integral role in helping to build our team and manage our way through unanticipated and unprecedented fiscal and public health crises.”

Dori Henry, Olszewski’s deputy chief of staff, will serve as interim chief beginning Sept. 15. Henry has held several positions in government including assistant secretary for public affairs for the U.S. Department of Labor.

Palmisano said, “The county executive is grateful that Dori has committed to serve as interim chief of staff through the end of this current term. Decisions regarding future staffing for the administration will be made as appropriate and contingent upon the outcome of November’s general election.”

Olszewski is running for a second term. He is being challenged by a former state legislator, Republican Pat McDonough.