zombie network spawn! help"

hi, i have look all over the internet to find a network enemy spawn script!. i have follow a tutorial that shows how to make a enemy spawner. and its works fine. but not on networking!, becouse if i have zombies after me. the other player cant see the zombies that following me, and i cant see the zombies that following him :((

here is the script..

 var spawnPoints : Transform[];  // Array of spawn points to be used.
 var enemyPrefabs : GameObject[]; // Array of different Enemies that are used.
 var amountEnemies = 20;  // Total number of enemies to spawn.
 var yieldTimeMin = 2;  // Minimum amount of time before spawning enemies randomly.
 var yieldTimeMax = 5;  // Don't exceed this amount of time between spawning enemies randomly.
 
 function Start(){
     Spawn();
 }
 
 function Spawn(){ 
    for (i=0; i<amountEnemies; i++){ // How many enemies to instantiate total
       yield WaitForSeconds(Random.Range(yieldTimeMin, yieldTimeMax));  // How long to wait before another enemy is instantiated.
 
       var obj : GameObject = enemyPrefabs[Random.Range(0, enemyPrefabs.length)]; // Randomize the different enemies to instantiate.
       var pos: Transform = spawnPoints[Random.Range(0, spawnPoints.length)];  // Randomize the spawnPoints to instantiate enemy at next.
 
       Instantiate(obj, pos.position, pos.rotation); 
     } 
 }