JavaScript - eliminar marcadores

<script type="text/javascript">

      function inicializar_mapa() {

        var marcadores = [

        ['Estas Aqui', <?php echo $mi_lat;?>, <?php echo $mi_lon;?>],

        ['<?php echo $tex1;?>', <?php echo $la1;?>, <?php echo $lo1;?>],

        ['<?php echo $tex2;?>', <?php echo $la2;?>, <?php echo $lo2;?>],

        ['<?php echo $tex3;?>', <?php echo $la3;?>, <?php echo $lo3;?>]

      ];

		var mapOptions = {

          center: new google.maps.LatLng(<?php echo $mi_lat;?>, <?php echo $mi_lon;?>),

          zoom: 16,

          mapTypeId: google.maps.MapTypeId.ROADMAP

        };

        var map = new google.maps.Map(document.getElementById("mapa_div"),

            mapOptions);

		var infowindow = new google.maps.InfoWindow();

      var marker, i;

      for (i = 0; i < marcadores.length; i++) {

	    var icon = "img/" + i + ".png";

        marker = new google.maps.Marker({

          position: new google.maps.LatLng(marcadores[i][1], marcadores[i][2]),

		  icon: icon,

          map: map

        });

        google.maps.event.addListener(marker, 'click', (function(marker, i) {

          return function() {

            infowindow.setContent(marcadores[i][0]);

            infowindow.open(map, marker);

          }

        })(marker, i));

      }

      }

    </script>