The Italian hostage killed by kidnappers in Iraq was a defiant "hero" in his final moments, Italian Foreign Minister Franco Frattini says.
Quattrocchi, an ex-baker, was trained to guard oil pipelines
The dead man was identified as Fabrizio Quattrocchi, 36, a security guard.
As the gunman's pistol was pointing at him the hostage "tried to take off his hood and shouted: 'now I'll show you how an Italian dies,'" he said.
Meanwhile, three Japanese hostages held in Iraq have been released, the government in Tokyo has confirmed.
The Arabic TV station Al-Jazeera has broadcast images of the three, who it said had been handed over safe and well to Muslim clerics.
Japan is investigating reports that two more of its citizens - freelance journalists - have been abducted.
In other developments:
- America's top soldier, Gen Richard B Myers, defends the US military's tactics during the siege of Falluja as "humane" and plays down the threat posed by Shia militants elsewhere
Gunmen kill an Iranian diplomat in Baghdad a day after Tehran sends a team to Iraq, reportedly to broker peace with Shia militants
Russian planes arrive in Baghdad to begin an evacuation prompted by a spate of abductions
Al-Jazeera also said it had video footage of Mr Quattrocchi's death, but would not broadcast it, because it was "too gruesome".
An Italian diplomat viewed the tape and relayed the details to Rome.
"He died a hero," Mr Frattini said, adding the family had authorised him to reveal the details.
Three other Italians, abducted on Monday, are still being held by the same group in Iraq. They were working as security guards for a US-based company.
Italian Prime Minister Silvio Berlusconi said the killing - the first confirmed hostage death in Iraq - would not affect the peace effort.
"They have destroyed a life, they have not cracked our
values and our efforts for peace," he said in a statement read out on Italian TV.
Mr Berlusconi's office said that an envoy, Gianni Castellaneta, would be sent to the region to try and obtain the release of the three other Italian hostages.
The BBC's Brian Barron in Rome says the government appears to be pinning its hopes on mediation by Iran.
The US-led coalition has said that around 40 foreigners are currently held hostage by militants in Iraq.
Mr Frattini said earlier that the kidnappers were "a group of bandits, not tied organically to any group".
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The hostage drama dominated Italian television on Wednesday evening, as it brought together some of the men's relatives and Mr Frattini.
At one point a relative turned to Mr Frattini and asked "What can we do about this?" - and there was nothing he could say, our correspondent reports.
Al-Jazeera apologised for not broadcasting the Italian's killing. An official for the TV told Italian television that Mr Quattrocchi had been shot in the back of the neck with a pistol.
The TV also said it had received a statement from the kidnappers, a group calling itself al-Katibat al-Khadra or the Green Battalion, in which it demanded the withdrawal of Italian troops from Iraq, the release of clerics held by Italian forces and an apology from Mr Berlusconi for allegedly insulting Islam.
They also threatened to kill the other three hostages "one by one".
Italian forces - the third largest contingent in the US-led coalition - are based in the southern city of Nasiriya, working on reconstruction.
Italy did not send combat troops during the war.
Last November a suicide truck bomb attack in Nasiriya killed 19 Italians - the country's worst single military loss since World War II.