WPF Gmap.NET adding large amount of markers

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C#

WPF

i'm using Gmap.NET with C# WPF, and i'd like to add a large amount of markers (~6k) on the map. But i still can't make add them asynchronously, Map is always freezing and not responding at all, until all markers will not be added...

Here is my code sample:

private void MainMap_Loaded(object sender, RoutedEventArgs e)
    {
        MainMap.Zoom = 12;

        LoadMarkers();
    }

    private async void LoadMarkers()
    {
        await Task.Run(new Action(() =>
        {
             for (int i = 0; i <= 6000; i++)
             {
                 Dispatcher.InvokeAsync(
                     new Action(
                         delegate()
                         {
                             PointLatLng point = new PointLatLng(GetRandomNumber(55.0000, 55.7510),
                                 GetRandomNumber(36.0000, 38.9999));

                             var currentMarker = new GMap.NET.WindowsPresentation.GMapMarker(point);
                             {
                                 currentMarker.Shape = new MarkerTemplate(this, currentMarker,
                                     string.Empty);
                                 currentMarker.Offset = new Point(-16, -32);
                                 currentMarker.ZIndex = int.MaxValue;

                                MainMap.Markers.Add(currentMarker);
                             }
                         }
                         ));
             }
         }));
    }