1505
one concern these men have in the waterways of iraq is the threat of an ambush , so there are five weapon stations on the special operations craft .
 ( attack: ambush,  waterways: place, men: target) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: declare bankruptcy, transfer ownership, transfer money, marry, transport, die, phone write, arrest jail, convict, sentence, sue, end organization, start organization, end position, start position, meet, elect, attack, injure, born, fine, release parole, charge indict, extradite, trial hearing, demonstrate, divorce, nominate, appeal, pardon, execute, acquit, merge organization, Arguments type: beneficiary, prosecutor, plaintiff, seller, victim, buyer, agent, destination, artifact, organization, recipient, person, place, origin, target, giver, adjudicator, attacker, vehicle, defendant, entity, instrument. 
Text: {0} 
Answer:
 ( attack: ambush,  waterways: place, men: target) 