CAMDEN, N.J. — In the summer of 2012, the year this city broke its own record for homicides, there were 21 people murdered here. This summer, there were six.

Just as remarkably, with shootings down 43 percent in two years, and violent crime down 22 percent, Osvaldo Fernandez now lets his sons walk to school alone. Nancy Torres abandoned plans to move to Florida. And parents from Center City Philadelphia are bringing their children here — notoriously one of the nation’s poorest, most crime-ridden cities — to play in a Little League that has grown to 500 players from 150 in its first season three years ago.

It has been 16 months since Camden took the unusual step of eliminating its police force and replacing it with a new one run by the county. Beleaguered by crime, budget cuts and bad morale, the old force had all but given up responding to some types of crimes.

Dispensing with expensive work rules, the new force hired more officers within the same budget — 411, up from about 250. It hired civilians to use crime-fighting technology it had never had the staff for. And it has tightened alliances with federal agencies to remove one of the largest drug rings from city streets.