BAGHDAD, Iraq - U.S. soldiers discovered the decapitated bodies of three Arab men yesterday along a highway north of Baghdad, while a suicide car bomb exploded at an Iraqi National Guard checkpoint south of the capital, killing two men and wounding 10 others, U.S. military and Iraqi officials said.
The explosion, in the town of Suwayrah, was part of a sharp spike in violence that has racked the country since Sunday. It followed two such suicide attacks in Baghdad on Tuesday, including one that killed 47 people and injured 114 others outside police headquarters in the capital.
Fighting between U.S. Marines and insurgents raged on in the western city of Ramadi, a center of Sunni resistance to the occupation. A health ministry spokesman said 13 people died in the clashes, including two women, and 17 were wounded.
The American military said a Marine died in combat Tuesday in Anbar province, which includes Ramadi and the virulently anti-American city of Fallujah. That brought to 1,018 the number of U.S. soldiers who have died since the invasion of Iraq in March 2003.
The new wave of attacks by the increasingly sophisticated insurgency is raising doubts about whether the Bush administration and the seemingly powerless Iraqi interim government can hold truly legitimate elections by the end of January.
Soldiers with the 1st Infantry Division discovered the three headless bodies about 7:30 a.m. local time on a highway west of Balad, a town rife with insurgents 50 miles north of Baghdad, said Master Sgt. Robert Powell, a spokesman for the division.
The heads were found "in the vicinity of the bodies," Powell said, and the soldiers secured the area as a "crime scene."
Iraqi police then arrived and are investigating the killings.
"The identity of the bodies had not been established," Powell said. He added that the victims were obviously Arabic and likely to be Iraqi, but that the police would be the ones to make the final determination.
Several militant groups, particularly ones in the so-called Sunni triangle area, have taken to beheading foreign hostages in an effort to drive fear into those cooperating with American troops and the interim government. Insurgents have taken dozens of foreign Muslims hostage, while at least four Westerners remain in captivity - two Italian women working for a nonprofit group and two French journalists.
Though the Italian and French governments have engaged in intense discussions to free the hostages, there has been no word on their whereabouts or condition.
A militant group said this week that it had seized two Australians and two East Asians from Samarra, an insurgent stronghold near Balad. But the Australian foreign office in Canberra said on yesterday that all 225 Australian nationals in Iraq were accounted for, Reuters reported.
In the town of Tal Afar, near the Syrian border to the north, families continued to return to their homes in small numbers after U.S. soldiers began lifting a siege on Tuesday. The soldiers invaded the ethnic Turkish town to flush out foreign fighters, military officials have said.
Mahmood Younis Saleh, the director of the main refugee camp in the nearby city of Mosul, said in an interview with an Iraqi reporter for The New York Times that he had 1,200 families in his camp, or about 6,000 people. Turkmen and Islamic groups were providing food, he added.
In other developments yesterday, the U.S. military released 275 detainees from the Abu Ghraib prison, the facility near Baghdad where U.S. soldiers allegedly abused Iraqi detainees, authorities said. Another 2,500 remain in custody there.
The Associated Press contributed to this article.