[
 {
  'city':'xx',
  'zone':'yy',
  'person_info':{
                  'person_on_zone':'p1',
                  'person_on_zone':'p2',
                  'person_on_zone':'p3',
                }
 },
 {
  'city':'xx',
  'zone':'ww',
  'person_info':{
                  'person_on_zone':'p1'
                }
 },
]

foreach ($val as $v){
                    $new_array['city'] = $v['city'];
                    $new_array['zone'] = $v['zone'];
                    foreach ($val as $v2){
                        $new_array['person_info'] = $v['person_on_zone'];
                    }
                }
                json_encode($new_array);