An express train crashed Friday into a Czech road bridge which collapsed during construction seconds before the train's passage, killing seven people and injuring dozens, rescue services said.

The freak nature of the accident was underlined when rail investigators later revealed that the train had been running 10 minutes late as it approached the metal bridge near Studenka in the northwest of the country.

The locomotive and six passenger carriages came off the tracks and were left a mass of twisted metal. Emergency services arrived at the scene to find dead, injured, bags and train seats scattered everywhere.

Rescue services spokesman Lukas Himpl said 67 people had been treated for injuries, of whom 13 were very badly hurt. A Polish man and five Czech women were killed in the crash and a seventh person died later in hospital.

"It's horrible. It's a disaster," said police spokeswoman Miroslava Michalkova-Salkova.

Fire brigade spokesman Zdenek Nytra said that rescuers had pulled all surviving victims from the wreckage.

The train was travelling at about 135 kilometres (85 miles) an hour as it approached the bridge, said Jan Kucera, a deputy director general of Czech railways.

The train was unable to stop in time, according to first accounts.

"The driver saw that the bridge was moving and was starting to fall," Kucera told reporters.

"He immediately slammed on the emergency brakes and hid in the engine compartment of the locomotive.

"Six seconds later there was the shock -- and it was still going at 120 kilometres an hour," the official added.

"There's a lot of damage," he said.

Teams of rescuers set about cutting victims free from the wreckage. The injured were taken to 10 hospitals across the region by helicopter and in ambulances.

The train had been travelling from the Polish city of Krakow to Prague and the Czech and Polish prime ministers Mirek Topolanek and Donald Tusk went immediately to the crash scene.

The injured included an eight-year-old girl who was very seriously hurt, according to doctors in Ostrava, who added that no-one from the girl's family had come forward by mid-afternoon.

Two French nationals were later discharged after treatment in nearby Bilovec, hospital administrator Martin Rais told AFP.

"If there had been the slightest suspicion of complications, for example cranial (head) trauma, then they would certainly have been kept in," Rais added.

Among the injured, there was also one man who spoke only English, CT public television reported.

There were about 400 people on the train at the time, including a large group of Czech, Polish and Slovakian youths making for a rock concert by British heavy metal band Iron Maiden at a Prague football stadium on Friday night.

"Our carriage was full of young people and we were having fun, then there was the crash, chaos. People were dying, they had no legs and arms. I am alive, I have been born again," one woman passenger told the CTK news agency.

The driver, who survived, told reporters: "There was nothing I could do."

"I will never get on a train again," he added, refusing to give his name.

Sixteen fire brigade units with 30 vehicles were sent to the scene, along with ambulances and helicopters.

It was the worst rail accident in the Czech Republic since June 1995, when 19 mainly young people were killed when a local train derailed at Kruna.

Full police and rail management investigations are underway.

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