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In northern Iraq , U . S . warplanes struck a convoy of allied Kurdish fighters and U . S . special forces Sunday in one of the deadliest friendly fire attacks of the war .
 Iraq: place; fighters: target; forces: target; warplanes: instrument
Given event type and trigger, please tell me the arguments of all the listed option. Output format is "name1: role1; name2: role2". 
Event type: attack 
  Option: victim, attacker, place, target, instrument 
Text: {0} 
Answer:
 Iraq: place; fighters: target; forces: target; warplanes: instrument