Error BCE0051

I made a script for the high score in my game and got some errors that looks like this.

Operator '>=' cannot be used with a left hand side of type 'Object' and a right hand side of type 'int'.

 #pragma strict
        var HS : int;
        var score;
        function Start () {
        var score : int = Timer.Timer;
        Debug.Log ("score");
        guiText.text = "" + HS;
        }
        function Update () {
    
        if (score >= HS) {
    
            guiText.text = "" + score;

  }    

}

Thanks in advance!