By BEN STOCKING, Associated Press Writer

HANOI, Vietnam - A section of a bridge under construction in southern Vietnam collapsed Wednesday, killing at least 34 workers and leaving dozens more trapped or injured, officials said.

The bridge was being built across the Hau River, a branch of the Mekong River, in the southern city of Can Tho.

The collapsed section was more than 98 feet tall and was situated above land on the river bank in Vinh Long province, said Vo Thanh Tong, chairman of the Can Tho people’s committee. The four-lane bridge was not yet open to traffic.

Images broadcast on Vietnamese television showed mounds of twisted steel and cables shrouded in dust and smoke. Dozens of workers in yellow helmets rushed about the wreckage, some carrying stretchers with bloody victims.

At least 34 people died, said Dang Van Tam, director of Central Can Tho General Hospital. More than 70 were injured, said Pham Van Dau, chairman of Vinh Long people’s committee.

“It was total chaos,” said Le Viet Hung, vice chief of the Can Tho police. “It sounded like a huge explosion. It’s the biggest accident I’ve ever seen.”

The exact number of missing was unknown, but on a normal day up to 140 people would work on the section that collapsed, Tong said. The official Vietnam News Agency reported that about 250 people were working there when the section buckled at about 8 a.m.

The 1.7 mile bridge was started in 2004 and expected to be finished next year. It was to be the largest suspension bridge in Vietnam and would greatly speed the trip across the river, which thousands now make daily by ferry.

Tong said workers had just poured concrete on the affected section Tuesday.

Japan provided a $218 million loan to finance the project, enough to cover 85 percent of the cost, said Yoshifumi Omura, of the Japanese Bank for International Cooperation in Hanoi. The Vietnamese government provided the rest of the funding.

HANOI (AFP) - - At least 18 people died Wednesday morning following the collapse of a bridge under construction in southern Vietnam, police said.

“The death toll of the accident has reached at least 18, while many other people are still stuck under the collapsed bridge,” Vu Duc Hung, head of Can Tho province’s water traffic police, told AFP.

Vietnamese national television VTV said more than 100 people have been injured, almost half of them in serious condition. Le Tan Hoc, director of the provincial department for Public Works, earlier said that at least 60 injured people had already been sent to hospitals.

About 250 workers and engineers were working on the Can Tho bridge when the accident happened, Hoc told AFP.

“The top priority now is rescue work,” said Ngo Thinh Duc, vice-minister of Transport, on VTV. “The most difficult thing now is to dismantle the huge fallen concrete blocks to save people underneath.”

He said about 150 military personnel have been mobilized.

Prime Minister Nguyen Tan Dung, currently in New York for the United nations general assembly, sent an urgent message asking authorities to instigate a major rescue operation and investigate the cause of the accident.

Officials did not immediately explained why the accident happened.

But the online VNExpress quoted police sources as saying a weak scaffolding system fell down, leading to the collapse of parts of the bridge that were only set in concrete on Tuesday.

The bridge is planned to cross the Hau river and link Can Tho and Vinh Long provinces. The accident occurred on the Vinh Long province side of the 16-kilometre bridge, and not in Can Tho province as previously said, Hung told AFP.

The newspaper website quoted Manh Hung, a worker and witness of the accident as saying workers heard a very loud noise at one end of the bridge.

“Workers started shouting. The scene was terrible as a giant concrete block fell onto so many people working underneath,” he said.

The online VNExpress said construction on the site started in September 2004. The 300-million dollar bridge, built with Official Development Assistance from the Japanese government, was expected to be completed next year, it added.

The Japanese embassy in Hanoi was not immediately available for comments.

“We have not known of any foreign engineers among the victims,” police officer Hung told AFP from the site.

LONDON (AFP) - - Criminal gangs are trafficking hundreds of children into Britain and forcing them to work in cannabis factories, with at least one child per week being found by police, a report said Sunday.

Campaign group End Child Prostitution, Child Pornography and the Trafficking of Children for Sexual Purposes (ECPAT) said there had been a five-fold increase in the practice in the last year alone.

Children as young as 13, many from Vietnam, were being brought to Britain to work as “slaves” for organised criminals to push production of the drug here to record levels.

They are forced to tend cannabis plants grown in suburban houses and often forced to sleep in cupboards, with little chance of escape for fear of being caught.

“There is clear evidence that there are young people who are trafficked, bought and sold, for the purpose of forced labour in cannabis production in the UK,” ECPAT’s director Christine Beddoe told the Independent on Sunday.

“In the past 12 months there has been a 500 per cent increase in the number of cases being reported to us. We now get told about one young person every week being removed from a cannabis factory.

“But nobody knows the true scale of the problem.”

Police believe the problem has emerged after organised crime gangs, many of them Vietnamese, moved to dominate the British cannabis market after the narcotic was downgraded from a Class B to Class C drug in 2004.

Declassification increased the potential rewards of growing and selling cannabis but decreased the risk of punishment. One police officer was quoted as saying cannabis was the “cash machine of organised crime.”

The newspaper said one three-bedroom house converted into a cannabis factory can yield up to 300,000 pounds a year.

Prime Minister Gordon Brown has indicated he is in favour of reversing the downgrade.

Peter Stanley, from the campaign group Stop the Traffic, was quoted as saying criminals were effectively picking the children “to order.”

“There is evidence that particular south-east Asian villages are targeted for specific trades, with Vietnam now known to specialise in boys for cannabis factories,” he said.

The campaigners said trafficked children found by police on raids at cannabis factories need better protection, as many have disappeared without trace soon after being taken into the case of social services.

They also said there was evidence many of those prosecuted in connection with such cannabis farms were in fact originally trafficked as children.