The national Queen’s Day holiday in the Netherlands is normally a joyful affair, but not this year.The royal procession in the city of Apeldoorn was disrupted, and all subsequent official celebrations cancelled after a car drove into watching crowds at speed, killing four people and injuring 13, five seriously. It remains unclear if it was an attack on Crown Prince Willem-Alexander and his wife, Princess Maxima, who were aboard an open top bus. They could only watch in horror as the car ended its journey by crashing into a stone monument in front of their eyes. “It’s a terrible shame what has happened. I was quite far away but I heard everything. We saw a car suddenly plunge into the parade, and that was all,” said an eyewitness. First aid workers fought to save the lives of some who had been mown down. Police said the driver of the car was arrested and was taken to hospital.. Queen Beatrice has expressed her shock and shared sense of pain with the victims’ families.