Object reference not set to the instance of a object


I keep getting the following error:

NullReferenceException: Object reference not set to an instance of an object
Turrent_AI.SearchTarget () (at Assets/Turrent_AI.cs:56)
Turrent_AI.FixedUpdate () (at Assets/Turrent_AI.cs:22)

But I can’t find the flaw in my code. Maybe someone knows?
Here’s my code:

void  SearchTarget (){
    Collider newTarget = null;
    Collider[] collidersInRange= Physics.OverlapSphere(transform.position,range);
    foreach(Collider currentCollider in collidersInRange)
        Collider currentEnemy = currentCollider;
		float healthCur = currentEnemy.gameObject.GetComponent<Stats>().health;
		float healthNew = newTarget.gameObject.GetComponent<Stats>().health;
        if (newTarget == null){
            newTarget = currentEnemy;
        else if (healthNew < healthCur){
            newTarget = currentEnemy;
    if (newTarget != null)
        target = newTarget.transform;

newTarget is null. You’re trying to use it on line 8 before setting it.