Deleting locked files in C#

Question

I'm running a listview to show thumbnails of a directory full of images in a MS Visual Studio application.

I'm trying to delete an image by selecting the images and pressing a button but for some reason the image is locked and won't delete. I suspect the thumbnail existing maybe the cause but can't figure a way around it

    private void MemberImagesDel_Click(object sender, EventArgs e)
    {
        if (MemberImages.SelectedItems.Count > 0)
        {
            if (MemberImages.SelectedItems[0].Text != null)
            {
                DialogResult dialogResult = MessageBox.Show("Are you Sure?", "Delete Image", MessageBoxButtons.YesNo);
                if (dialogResult == DialogResult.Yes)
                {
                    string filePath = Environment.CurrentDirectory + "\\Database\\Members\\" + MemberId.Text + "\\Images\\";
                    string fileName = MemberImages.SelectedItems[0].Text.ToString();

                    //Refresh images panel
                    MemberImages.Items.Clear();

                    ImageList imgs = new ImageList();
                    System.IO.Directory.CreateDirectory(filePath);
                    foreach (string item in Directory.GetFiles(filePath))
                    {
                        if (item != filePath + fileName)
                        {
                            //Add image to imagelist
                            imgs.ImageSize = new Size(128, 128);
                            imgs.Images.Add(Bitmap.FromFile(item));

                            FileInfo fi = new FileInfo(item);
                            MemberImages.Items.Add(fi.Name, imgs.Images.Count - 1);
                        }
                    }
                    MemberImages.LargeImageList = imgs;

                    File.Delete(filePath + fileName);
                }
            }
        }
    }

Has anyone encountered this issue before?