12657
The issue has been regarded as the most intractable in the Balkans since NATO bombers forced Yugoslav security forces to withdraw from Kosovo in 1999 , halting what international war crimes prosecutors say was a brutal campaign to force ethnic Albanians to flee .
 location contains: Balkans, Kosovo
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: ethnicity, place lived, geographic distribution, company industry, country of administrative divisions, administrative division of country, location contains, person of company, profession, ethnicity of people, company shareholder among major shareholders, sports team of location, religion, neighborhood of, company major shareholders, place of death, nationality, children, company founders, company founded place, country of capital, company advisors, sports team location of teams, place of birth 
Text: {0} 
 Entity Pairs:  Balkans, Kosovo 
Answer:
 location contains: Balkans, Kosovo