The hacking team hit Pokemon Go's login servers with a distributed denial of service (DDoS) attack leaving some players frustrated as they were unable to log in to the game, technology website TechCrunch reported.
(Also see: Pokemon Go Review)
The group said it would not stop the attack until representatives from Pokemon Go contacted them.
"No one will be able to play this game till Pokemon Go contact us on our website to teach them how to protect it!" the group wrote in a post on its website.
An OurMine member told TechCrunch that he or she is part of a three-person group of teenagers and that the team is trying to spread the word about security.
The group said that it is promoting stronger security and that "if it did not hack celebs and DDoS popular games, someone else would".
"We don't want other hackers attack their servers, so we should protect their servers," the OurMine member explained.
A DDoS (Distributed Denial of Service) attack works by flooding a server with traffic so that it cannot be accessed by legitimate users.
Apart from being hit by hackers, the game itself have struggled to keep its servers up and running.
Due the popularity and a number of people playing it at almost every time, Pokemon Go has suffered outages and glitches since its launch and with 26 new countries added to the game this weekend, the company would be having too much to handle.OurMine also claimed credit for compromising Twitter CEO Jack Dorsey's, Facebook chief Mark Zuckerberg's and Google CEO Sundar Pichai's social media accounts. The group also hacked the Twitter account of Evan Williams, the microblogging site's co-founder and former CEO.