Dutch police were investigating on Friday the motive of the suspected perpetrator in an apparently random fatal knife attack on a street in Rotterdam. The man attacked passers-by with a knife on Thursday evening in the Dutch port city. One person was killed and another was seriously injured. The suspected perpetrator was arrested. The police said the suspect is a 22-year-old man from Amersfoort, about 80 kilometres east of Rotterdam. No further details were given beyond that he had a police record. The fatality was a 32-year-old man. A 33-year-old man from Switzerland was seriously injured. Wi…