Another Siege of Maastricht (1673) took place during the Franco-Dutch War. In June 1673, Louis XIV laid siege to the city because French supply lines were being threatened. During this siege, Vauban, the famous French military engineer, developed a new tactic in order to break down the strong fortifications surrounding Maastricht. His systematic approach remained the standard method of attacking fortresses until the 20th century. On 25 June 1673, while preparing to storm the city, captain-lieutenant Charles de Batz de Castelmore, also known as the "comte d'Artagnan", was killed by a musket shot outside the Tongerse Poort. This event was embellished in Alexandre Dumas' novel "The Vicomte de Bragelonne", part of the D'Artagnan Romances. French troops occupied Maastricht from 1673 to 1678.