About 20 million internet-using children across 21 countries experienced sexual exploitation or abuse online within a year, UNICEF said Thursday. More than one in five surveyed children aged 12 to 17 reported at least one form of abuse. Most incidents occurred on social media, particularly Facebook, WhatsApp, Instagram, Snapchat and TikTok, while online gaming accounted for a smaller share. UNICEF said the global number of affected children likely reaches tens of millions, highlighting the scale of the threat.