Over 50 trains were delayed in the Indian capital city of Delhi on Wednesday, 20 January, as a thick fog enveloped the city, reducing visibility to less than 100m (330ft) in many places.

The fog descended on the previous night and became very dense around midnight due to lack of wind, reducing the general visibility to zero.

Rail operator Northern Railway cancelled as many as 12 trains in addition to the several trains that had already been cancelled until the end of January.

The Northern Indian region has been facing severe cold weather in the past month, with the minimum temperature on Wednesday recorded as 6.6°C.