In 1256, Daniel of Galicia openly defied the Mongols and ousted their troops in northern Podolia. In 1257, he repelled Mongol assaults led by the prince Kuremsa on Ponyzia and Volhynia and dispatched an expedition with the aim of taking Kiev. Despite initial successes, in 1259 a Mongol force under Boroldai entered Galicia and Volhynia and offered an ultimatum: Daniel was to destroy his fortifications or Boroldai would assault the towns. Daniel complied and pulled down the city walls. In 1259 Berke launched savage attacks on Lithuania and Poland, and demanded the submission of Béla IV, the Hungarian monarch, and the French King Louis IX in 1259 and 1260. His assault on Prussia in 1259/60 inflicted heavy losses on the Teutonic Order. The Lithuanians were probably tributary in the 1260s, when reports reached the Curia that they were in league with the Mongols.