Stop the Update function so death animation can complete.

Hello, i have an enemy character that has a death animation. When i kill the enemy, the death animation begins to play (In the "Death" function), stops halfway and repeats function Update and begins the chase animation again. How do i fix this?

var target : Transform; //the enemy's target
var moveSpeed = 3; //move speed
var rotationSpeed = 3; //speed of turning
var attackThreshold = 3; // distance within which to attack
var chaseThreshold = 10; // distance within which to start chasing
var giveUpThreshold = 20; // distance beyond which AI gives up
var attackRepeatTime = 1; // delay between attacks when within range

var maximumHitPoints = 5.0;
var hitPoints = 5.0;

private var chasing = false;
private var attackTime : float;

var myTransform : Transform; //current transform data of this enemy

function Awake()
{
    myTransform = transform; //cache transform data for easy access/preformance
}

function Start()
{
     target = GameObject.FindWithTag("Player").transform; //target the player
}

function Update () {

    // check distance to target every frame:
    var distance = (target.position - myTransform.position).magnitude;

    if (chasing) {
    Debug.Log ("player is close");
        animation.CrossFade("Walk");

        //rotate to look at the player
        myTransform.rotation = Quaternion.Slerp(myTransform.rotation,
        Quaternion.LookRotation(target.position - myTransform.position), rotationSpeed*Time.deltaTime);

        //move towards the player
        myTransform.position += myTransform.forward * moveSpeed * Time.deltaTime;

        // give up, if too far away from target:
        if (distance > giveUpThreshold) {
            chasing = false;

        }

        // attack, if close enough, and if time is OK:
        if (distance < attackThreshold && Time.time > attackTime) {
            animation.CrossFade("Attack");
            target.SendMessage( "ApplyDamage", 1);
            attackTime = Time.time + attackRepeatTime;
        }

    } else {
        // not currently chasing.
  Debug.Log("not close yet " + distance);
    animation.CrossFade("Idle");
        // start chasing if target comes close enough
        if (distance < chaseThreshold) {
            chasing = true;
        }
    }
}

function OnCollisionEnter (collision : Collision) { 

if(collision.gameObject.name==("SmallProjectile1(Clone)")) 

{ 

var contact : ContactPoint = collision.contacts[0]; 
var rotation = Quaternion.FromToRotation(Vector3.up, contact.normal); 

Hit(); 
} 

}

function Hit () {
// Apply damage
    hitPoints -= 1;

        if (hitPoints < 0.0) {
        Die();
}
}

function Die(){
    animation.Play("Death");
        chasing = false;
}

function Update()
{
   if(notPlayingDyingAnimation)
   {
      //Your normal update
   }
   else
   {
      //Your death animation code
   }
}