A police spokesman told local newspaper Hessische Niedersächsische Allgemeine (HNA) on Thursday that they had launched a child abuse investigation after a photo was posted on Facebook that shows an adult hand holding a cigarette to the mouth of a baby girl.
But thus far investigators are careful to note that they must still examine whether the person who posted the photo used their real name, and whether the person in fact lives in Kassel.
Bild reports that the man who posted the photo is believed to be the father of the child and lives in Kassel, but is originally from Bulgaria, according to his Facebook profile.
Bild further writes that after numerous complaints, the man took the photo down, but there were also other public photos on his profile depicting a young boy smoking.
HNA notes that in some countries, children smoking is a long tradition - even in Germany's neighbour Switzerland. There in Appenzell, children legally light up cigarettes, cigars and pipes during Funkensonntag (Spark Sunday) celebrations, as well as during cattle shows.
In Germany, the law is clear that smoking is only allowed for those 18 and older.