There's an old adage that goes: "the old fox understands the trap."

But if viral photos are any indication, it's the young fox that gets trapped inside of a metropolitan metro station.

The STM confirmed the authenticity of a photo posted to the Spotted: Montreal Facebook page, featuring a young, crying fox, standing on the tracks of the McGill metro station on the green line. 

In an email, an STM spokesperson confirmed that the fox was captured inside of the metro station by police on Friday, but that they have no details on how the creature found itself there. 

"It is extremely rare to see wild animals in our network," spokesperson Amelie Regis told CTV Montreal. 

Comments on the original Facebook post contained speculation as to whether the photo was doctored.

The caption of the photo, posted anonymously by one of the group members, indicates that an STM agent at McGill had spotted the fox wandering the metro for up to four days-- but this hasn't been confirmed.

The fox was released into the woods on Ile Saint-Helene. 

There's also no word on whether the fox was travelling with a valid Opus card.