A tanker truck spilled 12,000 kilograms of liquid chocolate across a highway, after it crashed through a traffic barrier near the western town of Slupca in Poland.

Local police said the truck belonged to a local candy maker, but it was unclear why the truck had slammed through the traffic barrier on highway A2 between the towns of Wrzesnia and Slupca.

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The tanker flipped over and landed across the road with its contents covering six lanes of traffic, blocking vehicles from passing in both directions. The driver was hospitalized with a broken arm, but no one else was hurt.

Vehicles left chocolate tire marks along several kilometers of highway before authorities closed down the highway.

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'A huge chocolate bar'

A cleaning crew armed with shovels, an excavator, and hot water pressure washers began chipping away at the chocolate that turned rock solid in the open air.

Rescue officials said the liquid chocolate was solidifying as it cooled and would need to be cleared away using large amounts of hot water.

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"It will take several hours," local firefighter chief Bogdan Kowalski told TVN24 television. "Once it hardens, chocolate's worse than snow."

"There's a 5-centimeter-thick layer of liquid chocolate that's gradually becoming solid," Kowalski said. "It looks like a huge chocolate bar," he added.

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law/ (AFP, dpa)