A knife-wielding assailant stabbed and killed a man in the Dutch port city of Rotterdam on Thursday night before he was overpowered by police and bystanders, police said.
Another person was injured in the incident, and the suspected attacker was hurt as he was subdued and arrested.
Witnesses told Dutch broadcaster NOS that the suspect shouted "Allahu Akbar" ("God is Greater" in Arabic) during the attack.
Police did not confirm this and said they were investigating the motive behind the assault.
The victim was a 32-year-old local man, police said on Friday.
Civilians takedown stabbing suspect
"The suspect was overpowered and arrested by bystanders and police officers", a police statement said.
De Telegraaf newspaper reported that a personal trainer who had been giving an outdoor class knocked the suspect unconscious with a squat stick that he had broken in two, and other bystanders threw chairs at him.
Both the surviving victim, a 33-year-old Swiss national, and the suspect were taken to hospital for treatment.
The suspect was a 22-year-old man from Amersfoort, a city located about 80 km (50 miles) from Rotterdam.
According to local media reports, the suspect stabbed his first victim in a parking garage beneath Rotterdam's Erasmus Bridge before moving to street level, where he fatally attacked another person.
Witnesses described the suspect as carrying two large knives and targeting random individuals.