BEIJING — A bridge under construction in an ancient Chinese city collapsed as workers removed scaffolding from its facade, killing at least 28 people, the government said today.

The 140-foot-high bridge spanning the Tuo River in the central Hunan city of Fenghuang collapsed Monday, the Hunan Administration of Work Safety said in a statement posted to the official Gov.cn Web site. The span in Hunan's Fenghuang county, intended for both pedestrian and vehicle traffic, had four decorative stone arches and was scheduled to open at the end of the month, the administration said.

At least 22 were injured, the official Xinhua News Agency said. An estimated 123 workers were at the site at the time.

Premier Wen Jiabao ordered a thorough investigation into the collapse of the 880-foot bridge, China Central Television reported.

The accident came less than two weeks after the collapse of a bridge in Minnesota that drew attention to aging transport infrastructure in the United States.

China Central Television showed bulldozers plowing through the rubble, overturning chunks of stone and concrete mixed in a tangle of steel reinforcement bars. News photos showed anxious and weeping villagers waiting for news about their loved ones.

Most of the people working on the bridge were local farmers, the agency said.

BAGHDAD — A suicide truck bomber struck a strategic bridge outside Baghdad on today, sending cars plunging into the river and killing at least 10 people in the second attack on the span in three months, police said.The attack came as 16,000 U.S. and Iraqi troops began a new operation north of the Iraqi capital targeting insurgents who have fled a crackdown in the restive city of Baqouba, the military said.The Thiraa Dijla bridge in Taji, a town near a U.S. air base some 12 miles north of the capital, came under attack around noon, police said, giving the casualty toll.The bridge, which stretched across a canal on the main highway that links Baghdad with the northern city of Mosul, was bombed three months ago and only one lane had reopened, according to the police officials, who spoke on condition of anonymity because they were not authorized to release the information.The attacker detonated his payload after going through an Iraqi army checkpoint about 40 yards away from the span.A number of cars plunged into the canal, which links the Tigris and the Euphrates rivers, and rescue efforts were under way, the officials said.The U.S. and Iraq operation farther north of the capital, dubbed Operation Lightning Hammer, began late Monday with an air assault and was part of a broader U.S. push.