Group 1 - The core issue involves a significant increase in mobile phone number registrations followed by rapid number portability and mass SMS sending, indicating potential telecom fraud activities [2][4]. - A criminal gang was identified, which was involved in sending over 100,000 fraudulent SMS messages within a short span of 10 days, using newly registered mobile numbers [4][6]. - Law enforcement agencies, specifically the Shenyang Public Security Bureau, successfully dismantled multiple criminal networks involved in SMS fraud, leading to the arrest of 21 suspects and the seizure of various illegal equipment [1][3][6]. Group 2 - The investigation revealed that the gang operated by opening multiple mobile accounts and sending deceptive collection messages, impersonating online lending companies to trick victims into transferring money [3][5]. - Following the initial arrests, further investigations led to the identification and dismantling of 9 additional criminal sites, resulting in the capture of 11 more suspects and the confiscation of equipment used for mass SMS sending [6]. - The police established a closed-loop operational model in collaboration with telecommunications departments to effectively analyze and combat such fraudulent activities [6].