MayorThe mayor is chief executive of a city.
In Pakistan chief minister is chief ex-active of a province not of a city . As Karachi is a city , it has no c.m.
Chief Magistrate of the ciry
The car and the city are named after Chief Pontiac in honor of him.
In most cities, the city council or the mayor appoint the chief of police.
The Chief of Police is not an elective office. Depending on the type of local government they are usually appointed by the chief executive of the city administration (Mayor - City Manager - City Council - etc).
Usually, the chief executive for a city within the United States of America is referred to as a Mayor.