The U.S. military said Tuesday they had found no signs of a U.S. Army translator missing after reportedly being kidnapped in Baghdad the night before, as troops continued to search the city's downtown on foot and by air.

The military said the soldier, who has yet to be identified by name, was last seen inside the fortified U.S. administrative compound in central Baghdad on Monday afternoon, after which he was believed to have left to visit relatives in the city.

He was reportedly at a relative's house when three cars pulled up and was grabbed by masked men who handcuffed him and forced him into one of the vehicles. One of the men then called a relative with the soldiers' cell phone, the military said. It didn't say whether a ransom demand was made.

U.S. and Iraqi forces threw a security cordon around Karradah on Monday night and Iraqis seeking to pass through the downtown area on Tuesday were turned away at roadblocks. Cars attempting to leave the area were searched while Army Kiowa OH-58 reconnaissance helicopters repeatedly circled overhead.

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U.S. soldiers carrying photocopies of the man's photograph searched houses and buildings across the area, which lies in a bend in the Tigris river.

Defense officials said the soldier, who was a linguist of American-Iraqi descent with the Provincial Reconstruction Team in Baghdad, was believed to have been abducted because he was seen being taken away. It was not clear who witnessed this.

American troops who raided Baghdad's al-Furat TV on Monday said they were looking for an abducted American officer of Iraqi descent who went to join family members in Karradah.

"We have not heard anything," Lt. Col. Christopher Garver, an American spokesman in Baghdad, said Tuesday. "We are sure U.S. forces are doing everything they can in the search."

In Washington, an Army official said the family has been notified.

The last time U.S. soldiers were reported missing was in June, when two soldiers were abducted during an attack on their checkpoint in Baghdad. The soldiers were later found dead, their bodies brutalized, the military said. One of the soldiers had been beheaded.

Al Qaeda in Iraq claimed responsibility for killing the soldiers, and said the successor to terror leader Abu Musab al-Zarqawi had "slaughtered" them, according to a Web statement that could not be authenticated.

The American military announced the deaths of four more servicemembers — a Baghdad-based soldier, two Marines and a Navy sailor. All but the soldier were killed Monday in the insurgent stronghold of Anbar province. The deaths raised to 91 the number of U.S. forces killed in October, the highest toll for any month this year and on course to surpass the October 2005 total of 96. Before that, the deadliest months were January 2005, at 107; November 2004 at 137 and April 2004, at 135.

Sectarian violence persisted in the southern Iraqi city of Amarah, with at least two more policemen shot to death early Tuesday. Militiamen loyal to al-Sadr have been hunting down officers aligned with a rival group in a new outbreak of Shiite-on-Shiite revenge attacks in the city.

The attacks came despite a public call by al-Sadr to halt the killings, suggesting that splinter groups were developing within his militia.

"I totally reject any Shiite-Shiite fighting or Sunni-Shiite sectarian fighting in Iraq under any pretext," al-Sadr said in an address to supporters Tuesday marking the beginning of the three-day festival of Eid al-Fitr, which marks the end of Ramadan. "Protecting Iraq is our main goal and the expulsion of the occupation troops from the country is our objective too."

Sunni Muslims marked the start of the festival on Monday.

Some Sunni political leaders have called for a truce during the Eid al-Fitr, and, possibly in part due to the holiday, relatively few deadly attacks on Iraqi civilians were reported Tuesday.

Two people were killed when a bomb exploded around noon in a market in the town of Qaim near the Syrian border, about 200 miles west of Baghdad, a local police captain said, speaking on condition of anonymity over safety concerns.

Another car bomb parked between a mosque and a coffee shop killed two people in northern Baghdad and injured 11 others, police Lt. Mohammed Khayon said.

In central Baghdad's al-Sadriyya market, a bomb hidden in a plastic sack outside a shop selling dairy products killed one person and injured seven others, police Lt. Ahmed Mohammed Ali told the associated press, adding that all wounded were rushed to al-Kindi hospital.

Around Iraq, 14 bodies of murder victims were found dumped on city streets or in the Tigris. All had been shot and most showed signs of having been bound and tortured, marking them as the likely victims of roving sectarian death squads.

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