The deadly attack, which took place in western Germany, has deeply shocked social media users. The incident came just one week after another young Afghani man was accused of an attempt to drown his German ex-girlfriend in a river in Berlin.
A 15-year-old boy, who reportedly comes from Afghanistan, has been arrested over suspicion of murdering a German girl of the same age during an argument on Wednesday, according to German media reports.
The incident took place in a grocery store in the German town of Kandel, Rheinland-Pfalz.
According to police, the two started quarreling when the boy suddenly pulled out a knife and stabbed the girl.
The young man was apprehended based on descriptions given by witnesses, while the severely injured victim was taken to hospital and died later that day.
The police have ruled out a terrorist motive. It remains unknown whether the boy is a refugee.
Social media users were quick to react to the news. Some of them slammed German Chancellor Angela Merkel for her migration policy.