Police had to launch a desperate late-night rescue operation in China after a section of highway collapsed into a giant sinkhole, trapping a car and killing at least one passenger.

The cavernous hole appeared along a busy stretch of Xiangjiang Road in Changsha, the capital of Hunan Province, central China, early this morning. The 30m-square pit swallowed a passing car, and at least one person died at the scene before emergency services could haul anyone to safety.

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© KeystoneUSA-ZUMA / Rex FeaturesCavernous: Police and emergency services have sealed off the section of road in Hunan Province, China, which swallowed a car this morning after collapsing in the early hours.
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© KeystoneUSA-ZUMA / Rex FeaturesRescue: A passer-by assesses the giant sinkhole after police had attempted to pull out the car and its passengers early this morning.

Chinese authorities did not describe the car which fell into the hole, or identify the victims, but said the vehicle was likely a BMW carrying three people, according to CNN.

The cave-in site was close to the Xiangjiang River, a major tributary of the Yangtze, China's longest waterway

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© KeystoneUSA-ZUMA / Rex FeaturesMystery: Investigators are still trying to establish the cause of the road collapsing in on itself on Thursday morning.

One rescuer with the local fire brigade described the sinkhole as being so deep, 'we cannot see the bottom of the pit with the naked eye'. Local police closed the road off as crowds gathered, with investigators trying to establish what caused the road to collapse.

A sinkhole is a natural depression in the Earth's surface which can be formed gradually or suddenly and occur worldwide.

They can vary in size, from 1 to 600 meters both in depth and diameter and form when the foundation below the surface layer dissolves. This commonly occurs when the rock below is dissolved by ground water. Limestone, carbonate rock, and salt beds are particular vulnerable to erosion. Meanwhile, the top layer of Earth usually stays intact.

According to the U.S. Geological Survey, Florida, Texas, Alabama, Missouri, Kentucky, Tennessee, and Pennsylvania are the states most affected by sinkholes.

While they often occur from natural causes, sinkholes can be man-made and caused by human activity. Groundwater pumping and construction are the most likely culprits.

Last month, residents in Florida, U.S, looked on in horror as a 40ft wide hole opened up in their street. It completely swallowed up the rear of this house in Hudson, Pasco County. The house collapsed into the ground like a toy house with its contents spilling everywhere.

The owner of the home was an elderly woman whose husband died a few years ago. She lived at the property on her own but was fortunately not at the house when the incident happened.