Slippery winter roads are sending cars into ditches and causing crashes on Germany's A2 highway in the northern part of the country.

Snow ploughs are working around the clock, but five centimetres of rapid snowfall gave drivers a hard time Sunday.

The A2 highway is a major east-to-west thoroughfare between Berlin and Hanover.

The German weather service is telling people to leave their vehicles at home, especially with the threat of black ice as the snow turns to rain.