Workers collect ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city. (Photos: Xinhua)

Workers collect ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

Workers collect ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

Workers collect ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

Workers collect ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

Workers collect ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

Workers collect ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

Aerial photo taken on Dec. 7, 2020 shows a worker collecting ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

A worker collects ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.

A worker collects ice from the Songhua River in Harbin, capital of northeast China's Heilongjiang Province, Dec. 7, 2020. Ice cubes collected from the frozen Songhua River will be used in decoration of the city.