2600
Four U . S . Army soldiers were killed when a suicide bomber attacked a military checkpoint today in Najaf .
 soldiers: victim; bomber: agent; checkpoint: place
Given event type and trigger, please tell me the arguments of all the listed option. Output format is "name1: role1; name2: role2". 
Event type: die 
  Option: victim, person, place, agent, instrument 
Text: {0} 
Answer:
 soldiers: victim; bomber: agent; checkpoint: place