Part of a recently opened bridge have collapsed in China's southwestern province of Sichuan along a highway linking the country's heartland with Tibet, local authorities say, but there are no reports of casualties.

Police in the city of Maerkang had closed the 758-metre-long Hongqi bridge to all traffic on Monday afternoon after cracks appeared on nearby slopes and roads, and shifts were seen in the terrain of a mountain, the local government said.

On Tuesday afternoon conditions on the mountainside worsened, triggering landslides, leading to the collapse of the approach bridge and roadbed, it added.

URGENT: Hongqi Bridge in #Sichuan Province in SW #China has collapsed on Tuesday afternoon, according to Chinese social media videos, after cracks were detected and traffic was suspended on

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