A couple went to river rafting on a hill station. Two days after their departure, the husband returned alone. He informed the police that her wife was swept away by the waves and died.
On the next day, police arrived to his doorstep and when he opened the door, they arrested him for murdering his wife. They told him that his travel agent had called them.
He was shocked. How did the travel agent know about the murder? Can you suggest how did he know ?