Police in Berlin say several people are being treated for shock after a helium passenger balloon was shaken around wildly by gusty winds for several minutes.

Police spokeswoman Kerstin Ziesmer said the balloon, which is a popular tourist attraction in downtown Berlin, was caught by the winds on Tuesday afternoon and people had to crouch inside the basket to avoid falling out. The balloon is tied to the ground with steel ropes but can be lifted to a height of 150 meters (500 feet).

Ziesmer said 17 people and the balloon's operator were in the basket at the time of the incident.

She said the operator managed to get the balloon safely back to the ground, but "it's not clear if anybody was injured."