The audio recording was found Wednesday on a Web site that serves as a clearinghouse of Islamic extremist statements. It is supposedly from Jordanian-born terrorist Abu Musab al-Zarqawi, whose network has been targeted by two U.S. airstrikes since Saturday.
Al-Zarqawi's group, Monotheism and Jihad, claimed responsibility for the beheading of American hostageand Kim Sun-il, a South Korean whose decapitated body was found Tuesday evening between Baghdad and Fallujah.
Hours later, U.S. forces launched an airstrike on what the Americans said was an al-Zarqawi hideout in Fallujah. Three people were killed and nine wounded, said Dr. Loai Ali Zeidan at Fallujah Hospital. It was the second U.S. airstrike on Fallujah since Saturday.
In other recent developments:
The woman and child were riding in a taxi, Iraqi police said. The policeman was killed while handling the bomb. Another man, his shirt off, was seen being led away in handcuffs.
Kim's body was found two days after he appeared on a videotape broadcast by Al-Jazeera television, pleading "I don't want to die" and begging his government to pull its soldiers out of Iraq. South Korea refused and said it would go ahead with plans to send another 3,000 troops here by August.
In the audiotape, the speaker thought to be al-Zarqawi told Iraq's interim prime minister, Iyad Allawi, that "we will continue the game with you until the end." The speaker said "we will not get bored" until "we make you drink from the same glass" as Izzadine Saleem, the Iraqi governing Council president killed last month in a car-bombing claimed at al-Zarqawi's group.
"We will carry on our jihad against the Western infidel and the Arab apostate until Islamic rule is back on earth," the voice said.
An official with Allawi's office dismissed the threat, saying it would not derail the transfer of sovereignty next week.
South Koreans poured out their sorrow and anger Wednesday over the beheading of Kim, 33, while president Roh Moo-hyun reaffirmed his resolve to dispatch more troops there and vowed to "deal sternly" with terrorism.
Kim's plight has gripped the country since Sunday, when the video released by his captors showed Kim pleading for the government to end its involvement in Iraq and pleading for his life.
The kidnapping of Kim, who worked for a South Korean company providing supplies to U.S. forces, stunned South Korea and prompted the Seoul government to order all non-essential civilians to leave Iraq as soon as possible.
Late Tuesday, the Arabic language satellite television channel Al-Jazeera broadcast a videotape of a terrified Kim kneeling, blindfolded and wearing an orange jumpsuit similar to those issued to prisoners at Guantanamo Bay, Cuba.
Kim's shoulders were heaving, his mouth open and moving as if he were gulping air and sobbing. Five hooded and armed men stood behind him, one with a big knife slipped in his belt.
One of the masked men read a statement addressed to the Korean people: "This is what your hands have committed. Your army has not come here for the sake of Iraqis, but for cursed America." South Korea is a U.S. ally in Iraq.
Al-Jazeera did not show the actual beheading, saying it was too graphic.
American troops found Kim's body between Baghdad and Fallujah about 5:20 p.m. Iraq time, South Korean Foreign Ministry spokesman Shin Bong-kil said. The body was identified by a photograph sent by e-mail to the South Korean embassy.
The grisly killing was reminiscent of the decapitation of Berg and of American helicopter technician, 49, who was beheaded by al Qaeda militants in Saudi Arabia. An al Qaeda group claiming responsibility posted an Internet message that showed photographs of Johnson's severed head.
President Bush condemned the beheading of Kim as "barbaric" and said he remained confident that South Korea would go ahead with plans to send the troops to Iraq. South Korea will be the third-largest troop contributor after the United States and Britain.
"The free world cannot be intimidated by the brutal actions of these barbaric people," the president said.