The app named Pokemon Go Ultimate, when downloaded and run, does not get installed as as Pokemon Go but as "PI Network", a report published in the Fortune said.
According to the report, the app froze phones when installed and ran, forcing users to restart the phone by removing the battery. The PI Network app seems to disappear after restarting the phone, however, it continues to run in the background and generates fake ad clicks, said Fortune.
It's not the first incident where malicious apps have been circulated in the name of the famous Pokemon Go game. Right after the launch of the game, many similarly named apps infected mobile phones.
Launched about more than a week ago, the Pokemon Go has become a sensation around the world. The game uses a phone's GPS technology with Google Maps to place virtual characters in real world location. The player then has to find and catch Pokemons using the map in the game.
Also read: Pokemon Go: How to install and play it in India, safely and securely
ESET also spotted several other malicious apps, including Install Pokemongo and Guide & Cheats for Pokemon Go.
The game's safety was earlier questioned when it asked iOS users to provide "Full control of Google account". However, the company later denied the allegation and said that it only sought basic profile permission from the user.
The specific apps highlighted by ESET seem to have been removed from Google Play Store, a search found several apps named with variations on Install Pokemon Go.
If you have installed any app named other than Pokemon Go, you can uninstall it by going to the phone's Application Manager.
Nintendo has created Pokemon Go in partnership with Niantic and Pokemon Company. The game so far has been released in the US, Japan, Australia, Philippines, New Zealand, Britain, and Germany. The game developers last week said they are trying to release the game in 200 countries. Due to the great number of people, Niantic has faced frequent server failures. According to reports, Pokemon Go is attracting more daily traffic than microblogging site Twitter.