Colliding Objects

Hello there, i need to destroy my gameobject when i click that object. The following code is working fine, but i want to destroy the objects with some particular distance. Which means if my object is far i need to go close and click that object.

 using UnityEngine;
 using System.Collections;
 
 public class Capture : MonoBehaviour 
 {
     RaycastHit Weapon_Hit;
     public int Rat, Frog, Snake;
 
     void Start()
     {
         Rat = 0;
         Frog = 0;
         Snake = 0;
     }
 
     void Update()
     {
         if (Input.GetButton ("Fire1")) 
         {
             if (Physics.Raycast (Camera.main.ScreenPointToRay (Input.mousePosition), out Weapon_Hit)) 
             {
                 if (Weapon_Hit.collider.tag == "Rat") 
                 {
                     Rat = Rat + 1;
                     Debug.Log ("Rat: " + Rat);
                     GameObject.Find("Rat_Count_Text").guiText.text = " " + Rat;
                     Destroy(Weapon_Hit.transform.gameObject);
                 }
                 if (Weapon_Hit.collider.tag == "Frog") 
                 {
                     Frog = Frog + 1;
                     Debug.Log ("Frog: " + Frog);
                     GameObject.Find("Frog_Count_Text").guiText.text = " " + Frog;
                     Destroy(Weapon_Hit.transform.gameObject);
                 }
             }
         }
     }
 }

-Prasanna