Aerial footage captured by a drone over a frozen lake in northwest China shows cracks in the ice that look like tree branches.
The rare phenomenon occurred in the icy layer that formed over Butterfly Lake, located in Gongliu County within the Xinjiang Uighur autonomous region.
The spidery appearance of the cracks is caused by sudden temperature drops, state-owned China Central Television (CCTV) reported. The broadcaster captured the footage on 17 January.
Butterfly Lake is a man-made lake shaped like the winged insect for which it is named, with a pedestrian bridge running down the middle.
