Imagine a city where a rush-hour backup might involve just a few cars, and the air is clean because just about everything runs on zero-carbon energy. That's the goal for the Swedish capital, Stockholm.
Swedish police say they have arrested the alleged driver of the truck that drove into a Stockholm crowd killing four on Friday. The 39-year-old man from Uzbekistan was already known to authorities. Saturday Swedish police say they found a suspect device in the truck.