Emit particles only for clicked instance of an object

Hi, I'm trying to create a script to emit particles when I click on an object ("bomb") with a specific tag("bomb"). The problem is that I have many of this objects and when I click on one of them, instance of particle is created on all of them, instead i'd want to emit particles only on the clicked object.

Where is my error?

 var explosion : Transform;
 
 var timeOut : float = 5.0;
 
 static var bomb : GameObject;
 
 function Update(){   
                              
     bomb = GameObject.FindGameObjectWithTag("bomb");
     MouseClick();
     
 }
 
 function MouseClick(){                            
     if (Input.GetMouseButtonDown(0)) {
         var ray : Ray = Camera.main.ScreenPointToRay (Input.mousePosition);
         var hit : RaycastHit;
         if (Physics.Raycast (ray, hit)) {
             
             if (hit.collider.tag == "bomb") {
                
                var instance = Instantiate(explosion, bomb.transform.position, bomb.transform.rotation);      
                
                Destroy(instance.gameObject, timeOut);
                
                Destroy(hit.collider.gameObject);
                
             }
          }
     }
     
 }