A task force looking into an accident at a MIRROR concert last week said metal fatigue of a suspension cord was likely the reason why it snapped, leading to the falling of a video panel that injured two dancers.

Lee Tsz-chun, an Assistant Director for Leisure and Cultural Services who led the task force, told reporters that officials had carefully examined the cable and ran tests on it.

"At the spot where the cable broke, there are signs suggesting that metal fatigue is highly likely to be the cause," he said.

"There are still a lot of tests to be done before we make our final conclusion. We will not rule out other possibilities and will investigate in different directions."

One of the dancers, Lee Kai-yin, who was struck in the head by the giant video screen, remains in a critical condition.

But officials said his vital signs are stable.