Seeing a dog riding the subway alone every day, an inquisitive passenger tracked him.
The Authorities
People would naturally get more worried about the lone dog walking through the metro. Where was he getting his food and drink, then? Should he receive an injury while on route, what would happen? He hardly bothered the other passengers since he stayed by himself most of the time. Their main worries were his health and welfare, quite simply. Some of the residents, without any other clear choices, came to the conclusion that contacting the authorities would be the smartest line of action. They wanted the dog taken away; they were just worried about making sure it was well cared for.
They were totally oblivious of the fact that, along with other residents, the authorities had already been informed a lot of information about the stray dog. They had also lately created a plan and implemented it.