Residents in Hanoi are reporting a surge in offers to purchase pre-activated SIM cards in bulk via Facebook groups. These “ready-to-use” SIMs, often advertised by weight, circumvent registration requirements and pose potential security risks. Authorities are concerned these cards could facilitate fraudulent activities, spam, and potentially criminal operations due to the anonymity they provide. The practice bypasses regulations designed to identify mobile phone users and prevent illegal activities. Experts warn that using unregistered SIM cards can leave individuals vulnerable to scams and identity theft. The sale of these SIMs is illegal under Vietnamese law, but enforcement remains a challenge as transactions occur online and outside of traditional retail channels. Authorities are investigating the source of these offers and working to shut down the groups facilitating the illicit trade.