BEIJING (AFP) - Cracks that appeared on a glass bridge in Yuntai mountain in the northern province of Henan "doesn't affect safety", park officials were quoted as saying about the incident that caused panic among visitors.

Thrill-seeking tourists in China got more than they bargained for when the cracks appeared in the glass-bottomed walkway suspended 1,080m over a canyon, reports said.

Images showing small cracks in the "skywalk" built around a mountain, which opened just two weeks ago, spread on social media along with doubts over its safety.

"When I was almost at the end (of the walkway), there was a sudden loud bang and a tremor beneath my feet," the state-run China Net cited one woman as saying on Tuesday (Oct 7).

The cracks resembled "winter frost on a window pane", the report said, and were apparently caused by a dropped stainless steel cup.

The glass made up of three layers is supposedly capable of supporting up to 800kg per square metre, the officials said.

The incident occured during China's hectic week-long national holiday period, when tens of millions take pleasure trips.