Winter weather is making its mark in many parts of the world. The Chinese capital, Beijing, is in the grip of its coldest spell for 20 years, seen in this photo of an ice-frosted bus.
In the Inner Mongolia region of China, a train hit a wall of snow more than 6ft (2m) high, leaving 1,400 passengers stranded as paramilitary police worked to free it.
But despite the transport disruption, this Beijing postman battled to make sure the day's mail got through.
And the freezing conditions were ideal for the Harbin International Ice and Snow festival in north-east China.
The South Korean capital, Seoul, has seen its heaviest snowfall since records began.
Dozens of people have died in a cold wave sweeping through northern India. Here a train is escorted by police in the Pulwama district of Jammu and Kashmir.
Europe has been gripped by freezing weather too. Here ice forms on twigs of a tree in the northern German city of Hamburg.
And in the UK, parts of the River Tyne in north-east England froze over with heavy snow elsewhere.
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