Digital security provider Avast has said that its security researchers discovered 21 adware gaming apps on Google's Play Store and reported those to the tech giant for necessary action.

Currently, 19 of the apps are still available on the Play Store, but Google was investigating the report.

Similarly to adware apps reported by Avast in June and in September, the adware is part of the HiddenAds family, displaying intrusive ads and luring users into downloading the adware by posing as gaming apps.

"The users need to be vigilant when downloading applications to their phones and are advised to check the applications' profile, reviews and to be mindful of extensive device permission requests,'' Jakub Vavra, a threat analyst at Avast, said in a statement.

The apps have been downloaded about eight million times so far based on SensorTower, a mobile apps marketing intelligence and insights company, estimates.

Numerous user reviews on the Google Play Store mentioned that the apps grabbed their attention through advertisements on YouTube, promising a different game than what the app ultimately offered.

Following the download, advertisements started flooding their phones.

Some of the games are: Shoot Them, Crush Car, Rolling Scroll, Helicopter Attack - NEW, Assassin Legend - 2020 NEW, Helicopter Shoot, Rugby Pass, Flying Skateboard and Iron, according to Avast.