An American civilian, a Nepalese man and at least two Arabs were abducted Monday by a band of gunmen who stormed a Baghdad home with a rocket-propelled grenade launcher and a machine gun mounted atop a pickup truck.

The kidnapped American was not identified. He became the 12th U.S. citizen reported kidnapped or missing in Iraq. Those taken Monday from the home in Baghdad's Mansour district were working for a Saudi firm.

The bold attack at sunset brought a violent close to the first day of voter registration in Iraq, a landmark that many Baghdad residents greeted warily.

Insurgents have threatened any Iraqi who cooperates with the interim government, and in recent days, they have carried out a wave of assassinations of senior officials. The latest came during Monday morning's commute, when gunmen killed the deputy governor of Baghdad, firing more than a dozen bullets into him as he sat in the back seat of his sedan.

Elsewhere, U.S. troops clashed with Sunni insurgents in Ramadi, where an Iraqi freelance television cameraman was killed, the Associated Press reported. American artillery pounded suspected insurgent positions in Fallujah, and residents reported fresh airstrikes and artillery attacks there late Monday, even as voter registration was scheduled to get underway in nearby towns and cities.

"Tomorrow the Americans will go to vote, but it's different for them: They feel safe, stable, have jobs and are feeling free and comfortable," Sameer Saeed, 38, said in Baghdad. "How can we have elections when the country is boiling like this? We do not feel safe, we do not have jobs, and they said they are going to attack the elections places."

Saeed, a former army officer, spoke in a neighborhood grocery store that doubled as a voter registration site. Under the plan, voter lists for January elections are being copied from the rolls of the food-rationing program that has been in place across Iraq for more than a decade.

The program covers every Iraqi, and starting Monday, those who showed up to collect their monthly handout of flour, oil and other staples were also to be handed a sheet listing everyone age 18 or older in their household. They were to be invited to offer corrections to the list. Otherwise, registration was automatic. No visit to a government office would be required.

But tensions in the capital remain so high that potential voters were keeping a distance from the process. In one shop, clerks refused to hand out forms while television cameras rolled, for fear of inviting reprisals from insurgents. At another distribution point for rations, one of 542 in Iraq, the owners confided plans to deliver the registration forms to their customers' homes, after dark.

"I will not give these applications to the people here. I will go to the families tonight and tomorrow night to their houses by my car and ask them to sign for me when they will receive it, so no one will say you did not give it to me," said one of the owners, who gave only his first name, Mohammed. "I think it is better like this, and safer. I do not want the people to gather here."

In the kidnapping, three carloads of men roared down a residential street just as Muslims gathered around tables to break their daylight fast, an obligation of the holy month of Ramadan.

The kidnappers killed an Iraqi guard after forcing him to open the gate to the residential compound, surrounded by the eight-foot-high wall common to Iraqi homes. His body was found beside his AK-47. Inside the house, police discovered the body of a man believed to have been among the kidnappers.

Neighbors drawn by the sound of heavy gunfire hollered up to the roof to a terrified man wearing a flack vest. The man, who neighbors recognized as a foreigner who lived in the house, refused to be coaxed down. A U.S. official confirmed that one American escaped capture.

The attack occurred about 500 yards from the house where two Americans and a British man were kidnapped last month. All three were later beheaded by extremists. That assault spurred Westerners working in Iraq to reassess their own security, and most abandoned private homes as unsafe.

Neighbors said the house targeted Monday had been occupied for about five months by a foreign company that also maintained three or four other homes in the Mansour neighborhood. The company was identified as Saudi Arabian Trading and Contracting Co., a supplier to U.S. forces in Iraq, according to the Reuters news agency.

Attacks on foreigners have risen sharply in recent weeks, and insurgents warned that they will increase further if Iraq's interim government directs U.S. forces to carry out a major offensive on Fallujah and Ramadi, cities controlled by insurgents.

Followers of Abu Musab Zarqawi, the Jordanian who recently pledged fealty to Osama bin Laden, on Saturday posted fliers on mosque walls in Fallujah urging fighters to take the battle to other cities, and residents say bands of insurgents have shifted to the capital to carry out kidnappings and attacks on hotels housing Westerners.

Iraqi and U.S. officials say Fallujah must be returned to government control before elections can go forward. Negotiations aimed at averting a showdown continued Monday.

Fighting flared again in Ramadi, about 60 miles west of Baghdad. The slain cameraman, Diaa Najm, was killed by a shot to the head while filming a firefight near his home for Associated Press Television News. Najm was the 24th journalist killed in Iraq.

Marines also continued to mass forces around Fallujah, briefly pounding the city with artillery but not yet moving ground units forward.

"We have a plan. We're not going to execute it until we're asked to," said Nathan Braden, spokesman for the 1st Marine Expeditionary Force. "The reason we're in this country is to facilitate the Iraqi government. We're not here to kill people. They just keep shooting us. What can you do?"

Correspondent Jackie Spinner reported from near Fallujah. Special correspondent Omar Fekeiki in Baghdad contributed to this report.

U.S. Marines engage in a gun battle with insurgents in the town of Ramadi.