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.

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.

Swedish police have arrested a teen suspect after three youths aged from 15 to 20 were killed in a shooting at a hair salon, authorities said Wednesday, amid rising concern over gang violence in the Scandinavian nation.