Don't you dare mess with granny

The colourful language in the song was a step too far for some in Germany. Photos: visualhunt.com

A group of children singing a song about their grandmothers has unleashed controversy in Germany, bringing several hundred people onto the streets of Cologne in rival protests that descended into scuffles on Saturday.

The offending video, which was an attempt at satire by public broadcaster WDR, features a group of smiling young girls lambasting their grandmothers to the tune of a well-known German children's song.