Builders working on York's new Davygate shopping centre jumped clear when a large concrete flooring slab collapsed into an underground tunnel today.

The workers from Shepherd Construction were pouring concrete into a five-metre square metal frame when it started to move, but all managed to escape without injury.

One of the builders at the scene, who asked not to be named, said: "I was sitting on the roof when I heard other workmen shouting that the structure was bending.

"The lads working on the floor jumped off about 30 seconds to a minute before it collapsed. The noise was like in a movie, like an earthquake."

An investigation has been started by Shepherd Construction, and the Health and Safety Executive has been informed. A spokeswoman for Shepherd said: "The floor slab would have formed part of the new parking area.

"It started to sag very slowly, so the people working on pouring the concrete were able to escape."

She said there had been no one working in the underground tunnel when the incident took place.

Work was continuing as normal for the rest of the day.

Health and Safety Inspector Rom(correct) Naplocha said: "This appears to have been a dangerous occurrence, which is reportable by law.

"Shepherd Construction contacted us and whether we investigate depends on further information we receive."

Building work on the first phase new shopping centre is scheduled to be completed by September and the shops could be open by Christmas.

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