The next major battle to feature gunpowder weapons was during a campaign led by the Mongol general Bayan, who commanded an army of around two hundred thousand, consisting of mostly Chinese soldiers. It was probably the largest army the Mongols had ever utilized. Such an army was still unable to successfully storm Song city walls, as seen in the 1274 Siege of Shayang. Thus Bayan waited for the wind to change to a northerly course before ordering his artillerists to begin bombarding the city with molten metal bombs, which caused such a fire that "the buildings were burned up and the smoke and flames rose up to heaven." Shayang was captured and its inhabitants massacred.