More than 200 vehicles were involved in a pile-up on a bridge in the Chinese city of Zhengzhou in heavy fog, rescuers and the CCTV state broadcaster reported.
At least one person was killed.
Cars and trucks could been seen crumpled and piled on top of each other on the Zhengxin Huanghe bridge in pictures and videos posted on social media.
One car was jack-knifed in the middle of a pile in a picture taken from CCTV footage.
"This is too scary. Full of people here, I don't think we can get off the bridge," one person can be heard saying in one video clip.
Many of the injured were trapped in their vehicles and the fire department sent 11 fire trucks and 66 fire rescue personnel to help, state media reported.
Visibility in many areas was less than 500 metres on Wednesday morning and down to 200 metres at times, the meteorological service said.
CCTV reported that cars travelling in both directions over the bridge, a major crossing of the Yellow River, were involved in numerous crashes.
Police later closed the bridge to all traffic.
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