WASHINGTON (CNN) -- The head of Blackwater USA on Sunday rejected a mounting series of reports suggesting the private contractor's security guards opened fire on innocent Iraqi civilians last month.



Blackwater CEO Erik Prince said Sunday that guards "definitely" faced insurgent fire September 16.



"There was definitely incoming small arms fire from insurgents" in the September 16 incident in Baghdad, founder and CEO Erik Prince told CNN's Wolf Blitzer on "Late Edition."



There was no "deliberate violence," committed by Blackwater employees, he added.



Still, when asked whether it is possible someone with Blackwater "screwed up" in the incident, Prince replied, "Certainly it's possible."



He said he expects the FBI investigation to provide many answers.



Meanwhile, U.S. and Iraqi officials continue discussing Baghdad's demand that Blackwater be expelled from Iraq within six months, The Associated Press reported Sunday.



American officials are also coming up with ways to fill the security gap if Blackwater is forced to leave, AP reported.



Blackwater guards, protecting U.S. officials in Iraq, face dangerous circumstances every day and have navigated the vast majority of those situations without any violence, Prince told CNN.



The guards just try to do their jobs, and are "not trying to make any trouble," he said.



The Iraqi government accuses Blackwater guards of opening fire without provocation on civilians in a crowded area in Baghdad on September 16, killing 17 and wounding 27.



Survivors told FBI investigators Blackwater guards shot at civilians presenting no threat.  Watch a Blackwater witness describe his account »



The first U.S. soldiers to arrive on the scene after the incident told military investigators they found no evidence contractors were fired upon, a source familiar with a preliminary U.S. military report told CNN.



The soldiers found evidence suggesting the guards fired on cars attempting to leave and found weapon casings on the scene matching only those used by U.S. military and contractors, the military source said.



But Prince on Sunday told CNN, "In the incident reports I've seen, at least three of our armored vehicles were hit by small arms fire, incoming, and one of them damaged, which actually delayed their departure from the traffic circle while they tried to rig a tow.



"So there was definitely incoming small-arms fire from insurgents."



He added, "I guarantee our guys weren't shooting at each other."



And he said the traffic circle is very big, so those first soldiers on the scene would have needed "almost a battalion to secure that entire area, to do a thorough crime scene type investigation."



"So the jury is still out. We'll see what the FBI report comes up with, but I'm confident that the kind of people we have out there are proven military professionals," Prince said.



Iraqi government spokesman Ali al-Dabbagh accused Blackwater of "a deliberate crime against civilians," and said the company "should be tried in court, and the victims should be compensated."



A Philadelphia law firm has filed suit in federal court against Blackwater on behalf of the families of three Iraqis killed and one wounded in the in the incident, which occurred in and around Baghdad's Nusoor Square.



The suit claims Blackwater "created and fostered a culture of lawlessness amongst its employees, encouraging them to act in the company's financial interests at the expense of innocent human life."



Prince called the lawsuit "politically motivated" for "media attention," and rejected the depictions of his company.



"In Baghdad, the most dangerous city in the world, to say that it was a callous, rampant, evil action, you know, when the guys get it right 99 out of 100 times and don't have to use any force or any violence at all, I think they are doing very well," he said. E-mail to a friend
Who said Blackwater guards killed 17 without provocation? Who may be expelled? What did Erick Prince say about arms fire from insurgents? What did the Iraqi government say? Who may be expelled from Iraq? What was not deliberate? Who said the quote?
Iraqi government Blackwater that guards "definitely" faced accuses Blackwater guards of opening fire without provocation on civilians in Blackwater violence," Erik Prince
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