How to animate Enemy

I have downloaded a free zombie model with animations.I downloaded it from here . It contains idle,walking, attacking animations in fbx format. I also found a script to follow the player but it does not do any animation, it just follows the player like a ghost.
Please help about animating it.
Here is the code-

var Distance;
 var Target : Transform;
 var lookAtDistance = 25.0;
 var chaseRange = 15.0;
 var moveSpeed = 5.0;
 var Damping = 6.0;
 var controller : CharacterController;
 var gravity : float = 20.0;
 
 private var MoveDirection : Vector3 = Vector3.zero;
 
 function Start ()
 {
 
 }
 
 function Update ()
 {
     Distance = Vector3.Distance(Target.position, transform.position);
     
     if (Distance < lookAtDistance)
     {
         lookAt();
     }
     
     if (Distance > lookAtDistance)
     {
         
     }
 
     else if (Distance < chaseRange)
     {
         chase ();
     }
 }
 
 function lookAt ()
 {
     var rotation = Quaternion.LookRotation(Target.position - transform.position);
     transform.rotation = Quaternion.Slerp(transform.rotation, rotation, Time.deltaTime * Damping);
 }
 
 function chase ()
 {
     GetComponent(NavMeshAgent).destination = Target.position;
 }

You will first need to create a animator controller for your Zombie Character idle,walking, attacking.
You can check the documentation here http://docs.unity3d.com/Manual/MecanimAnimationSystem.html