Firefighters in the town of Werl in western Germany tackled an unusual emergency late on Monday when a tank at a local firm making liquid chocolate overflowed and poured out onto a street.

"About a tonne of chocolate ran out into the yard and from there onto the street," a spokesman for the Werl fire department said in a statement.

The firefighters closed off the street and shovelled the chocolate - about 10 square metres - to one side before a specialist cleaning company cleaned the road.

"Despite this heartbreaking incident, it is unlikely that a chocolate-free Christmas is imminent in Werl," the fire department said.