Rule of thumb. If you have to shimmy, squeeze, or finagle yourself into a closed off area to hunt Pokemon, maybe just don't. Trust me, that Geodude or Caterpie is just not worth it.
Four teenage boys did not abide by that mantra, and thus found themselves stuck in an underground cave system that spans 72 square miles. They entered what are known as the Box mines in Hawthorn, Wiltshire, scouting the series of underground tunnels for Pokemon. Unfortunately, they couldn't get back out, but they lucked upon an opening that allowed service to their cell phones and called for help.
Damien Bence of the Dorset and Wiltshire Fire and Rescue offered a few details about the situation as well as the rescue (via BBC).
"The fire service doesn't have a statutory duty to enter underground systems, normally we would call on other experts such as mine rescue, but in this case there's lots of local experts and guides, and we used one of those. We managed to lower down water and radios so they could communicate with us."
Bence also had some thoughts on the game that got the teens into this situation.
"It's [Pokemon] beyond me. I don't quite understand it, it seems to be a bit of a phenomenon at the moment. They were looking for these Pokemon creatures and surprisingly they didn't find any, but it's obviously leading people into dangerous situations, such as this, and things are likely to escalate if people are going to follow the rules of this game."
Needless to say, don't look for Pokemon in underground tunnels. It's just a bad idea.