passage: Before crossing to Asia , Alexander wanted to safeguard his northern borders .
  In the spring of 335 BC , he advanced to suppress several revolts .
  Starting from Amphipolis , he traveled east into the country of the " Independent Thracians " ; and at Mount Haemus , the Macedonian army attacked and defeated the Thracian forces manning the heights .
  The Macedonians marched into the country of the Triballi , and defeated their army near the Lyginus river ( a tributary of the Danube ) .
  Alexander then marched for three days to the Danube , encountering the Getae tribe on the opposite shore .
  Crossing the river at night , he surprised them and forced their army to retreat after the first cavalry skirmish .
  News then reached Alexander that Cleitus , King of Illyria , and King Glaukias of the Taulanti were in open revolt against his authority .
  Marching west into Illyria , Alexander defeated each in turn , forcing the two rulers to flee with their troops .
  With these victories , he secured his northern frontier .
  While Alexander campaigned north , the Thebans and Athenians rebelled once again .
  Alexander immediately headed south .
  While the other cities again hesitated , Thebes decided to fight .
  The Theban resistance was ineffective , and Alexander razed the city and divided its territory between the other Boeotian cities .
  The end of Thebes cowed Athens , leaving all of Greece temporarily at peace .
  Alexander then set out on his Asian campaign , leaving Antipater as regent .
query_and_answer: What did Alexander do when he learned that Cleitus , King of Illyria and King Glaukias of the Taulanti were in open revolt against his authority ? || Gave up
evidences: News then reached Alexander that Cleitus , King of Illyria , and King Glaukias of the Taulanti were in open revolt against his authority . Marching west into Illyria , Alexander defeated each in turn , forcing the two rulers to flee with their troops . With these victories , he secured his northern frontier .