A huge wall collapsed Monday at an unfinished terminal at Dubai's airport, killing at least eight workers and injuring dozens more, witnesses said.

Workers who spoke on condition of anonymity said they saw up to 40 injured people being taken away, but the toll could not be immediately confirmed. Airport spokeswoman Lavina Dixit Chatterjee issued a lower toll, saying five workers were killed and 12 were injured.

Two Dubai (search) hospitals said they had received 10 and 12 injured workers apiece, making for a total of 22. Nine were in serious condition.

At least eight people were killed at the scene and some died in the hospital, said an official of Al-Naboodah Laing O'Rourke (search), the main contractor at the site, who spoke on condition of anonymity.

Between 150 and 200 men were said to be on the site at Terminal 3 when the reinforced concrete wall collapsed at 10:45 a.m.

"The wall fell down, and we all ran to help, but there wasn't anything we could do," said worker Daljinder Singh. "Rescue teams were very late in coming. It took them maybe one hour to arrive."

"I saw many, many of my colleagues being taken away," another worker said, before a supervisor told him to be quiet.

The dead were taken to a state morgue, where a police spokesman referred all calls to airport officials.

Police cordoned off the construction site, prohibiting reporters from entering or taking photographs. A photo released by the airport showed a high wall, with a large section that had fallen.

Several companies are involved in the design and construction of the terminal, including the French company Aeroports de Paris International (search), according to an ADP official in France who spoke on condition of anonymity.

However, the site where the accident occurred — Concourse 2 — was not designed or being built by ADP, the official said. ADP was in charge of construction of the main hall of the terminal and several other areas, the official said.

The company also operates Charles de Gaulle airport in Paris, where part of a terminal collapsed in May, killing four people.

The Dubai facility bills itself as "the world's fastest growing airport" and is engaged in a $4.1 billion expansion that will enable it to boost its capacity from 22 million passengers per year to 60 million per year when it is completed in 2018.

Airport spokeswoman Chatterjee said she could not say whether the accident will delay the project.