This is the shocking moment two dust devil tornadoes formed near Hong Kong Airport.

Footage shows a brownish weather phenomenon taking shape on a construction site next to the runway in Chek Lap Kok on July 14.

About five seconds after the first whirlwind disappeared, a second one formed nearby but it was apparently weaker and lasted shorter.

No one was reported hurt from the incident. The whirlwind also did not leave any damage.

Dust devils are a type of whirlwind tornado that form when the sun heats a patch of land and the air above becomes warmer and rises quickly.

Cooler air then moves into the low-pressure gap left by the rising warm air. The new drafts of cooler air also heat up, rise and the cycle continues, picking up dust and debris making the spiral visible.