Authorities in various cities across China have cautioned minors against using encrypted messaging apps, urging parents to delete the software from adolescents’ smartphones to avoid them being exploited by criminals. The move come as the country continues to crack down on the apps, which can bypass Beijing’s prying eyes.

The fresh round of warnings have hinted at youngsters’ misbehavior and manipulation by criminals, with police across the country expressing concerns over the use of encrypted messaging apps earlier this month.

The notices covered a flurry of domestic apps, such as BatChat, Shimida, Seagull and Lianxin, as well as foreign texting apps like Telegram, WhatsApp and Twitter, all three of which cannot be accessed directly in China. The app watchlist issued by multiple police departments varies slightly, with some including WhatsApp or Twitter.