Exit modal after return of result

After deleting and returning to index ...

    [HttpPost]
    [ActionName("Delete")]
    public ActionResult DeleteConfirmed(int id)
    {
        _unitOfWork.UserRepository.Remove(id);
        _unitOfWork.Salva();
        return RedirectToAction("Index");
    }

My modal does not go out ..

btnDeleteCode

<div><divclass="modal-footer">
        <button class="btn btn-default" data-dismiss="modal">CANCELAR</button>
        <input id="btnDelete" class="btn btn-danger" type="submit" value="EXCLUIR" />
    </div>

How do I get it out automatically?