Iraqi militants executed one of four Italian hostages, officials in Rome confirmed Wednesday — the first known execution of any of the 22 foreigners being held in Iraq.

The killing could further heighten fears among international aid workers, contractors and journalists, some of whom are already restricting their activities in the country.

Earlier Wednesday, a French journalist was freed after a four-day hostage ordeal and Russia announced it would evacuate its citizens.

The militants who killed the Italian hostage demanded the withdrawal of U.S. forces from Iraq and threatened to kill the three other hostages, Al-Jazeera (searchreported.

The Arab TV network reported it had video of the killing but did not broadcast it because it is too graphic. Al-Jazeera did show footage of the four Italian security guards sitting on the ground, holding up their passports and surrounded by armed men.

The Italian ambassador to Qatar, where the network is based, watched the video and confirmed the man killed was Fabrizio Quattrocchi, one of the kidnapped Italians, Italian Foreign Minister Franco Frattini (searchsaid.

Frattini said the government would do "what is possible and impossible" to free the remaining three.

Italian Premier Silvio Berlusconi (searchsaid, "They have cut short a life. They have not damaged our values and our commitment to peace."

The French television journalist was freed unharmed at a mosque in Baghdad, saying he suffered constant movement and threats to his life.

Alexandre Jordanov (search), who works for Capa Television in Paris, was kidnapped Sunday while videotaping a U.S. military convoy under attack. He was traveling with cameraman Ivan Ceriex, who was released the next day.

Jordanov, 40, said his abductors switched his location eight times, passing him from one armed group to another.

"It was: 'We're going to cut your throat' to 'You're part of the Mossad,"' Jordanov said, referring to the Israeli secret service.

Herve Chabalier, president of Capa, told LCI television that negotiations with Sunni religious authorities led to Jordanov's release.

A U.S. spokesman said Tuesday that 40 foreigners from 12 countries are being held by kidnappers — but an Associated Press count put the number at 22, with Wednesday's release of the French journalist and the apparent abduction of two Japanese in a Baghdad suburb.

The Japan Visual Journalist Association received an e-mail from unidentified "Iraqi sources" who arranged a car for the two Japanese to the site of an emergency landing of a U.S. military helicopter on Wednesday. The freelance journalist and an aid worker were grabbed by gunmen, the e-mail said.

Japan said it was investigating the report. Three other Japanese are among the foreigners abducted and still being held.

"The reports are unconfirmed, but it appears two more people had been kidnapped," Foreign Minister Yoriko Kawaguchi told a parliament committee. She added the government was trying to gather details about the latest incident.

American experts, meanwhile, were conducting tests to determine whether four bodies discovered west of Baghdad are the remains of private U.S. contractors missing since an assault on their convoy Friday.

One of the missing — Thomas Hamill, a 43-year-old truck driver — is known to have been abducted. His captors have threatened to kill and mutilate him unless U.S. troops ended their assault on Fallujah. The deadline passed Sunday with no word on his fate.

The Russian Embassy in Baghdad was preparing a list of about 800 specialists to be evacuated.

The move comes after three Russian and five Ukrainian employees of a Russian energy company were kidnapped by masked gunmen who broke into their Baghdad house on Monday. They were released unharmed the next day.

The four Italian security guards were abducted Monday. The militants' videotape was accompanied by a statement from a previously unknown group, the Green Battalion, said it would "kill the three remaining Italian hostages one after the other, if their demands are not met," Al-Jazeera said.

The group demanded the withdrawal of U.S. forces from Iraq, an apology from Berlusconi, and the release of religious clerics held in Iraq.

Berlusconi on Tuesday ruled out any withdrawal of troops.

Three of the Italian captives were working for a U.S.-based company while a fourth was employed by a Seychelles-based firm, Frattini said.

He stressed that the four Italian hostages were not members of Italian intelligence, and that the abductors were "terrorists and killers" who were "out of control" — not members of any organized resistance.

Italy is the third-largest coalition partner in the occupation force. Italy didn't send in combat troops during the war. Its forces are based in the southern city of Nasiriyah, working on reconstruction.

In November of last year, Italy suffered tragic losses when a truck bomb attack in Nasiriyah, a city in southern Iraq, killed 19 Italians.

On Thursday, the Philippines ruled out withdrawing its small contingent of soldiers and police from Iraq, but said it may evacuate other Filipinos from the Mideast nation.

President Gloria Macapagal Arroyo said about 50 troops in central Iraq was operating in an "safe and secure" area, but as a precaution, they were being restricted to their camps.

Arroyo had said on Wednesday that her government was studying whether to withdraw troops from Iraq.