A 16-year-old boy was arrested on suspicion of murder in Sweden, the authorities said on Wednesday, after three people were fatally shot the day before, in the latest blow to a country grappling with high levels of gun violence compared to its European peers.

A Swedish teenager has been arrested after three people were shot dead in a hair salon in Uppsala. The victims, aged between 15 and 20 years old, were killed on Tuesday afternoon in the university city north of Stockholm.

Uppsala is home base for Sweden's two most notorious gang leaders, Ismael Abdo and Rawa Majid, who are both believed to be orchestrating operations from abroad.