STOCKHOLM — Swedish police said Saturday that they believe they have captured the man accused of turning a beer truck into a weapon a day earlier by driving it into a crowd of pedestrians in a rampage that left four people dead. Authorities did not divulge the man’s name but said he is a 39-year-old from Uzbekistan who had been known to security services as “a marginal character” for the past year. Police said that when they first investigated him, they had found no connections to extremism. Authorities did not say when the man had come to Sweden. The arrest...