Speaking during a conference in Naivasha, Communications Authority Telecommunications Compliance Manager Derrick Khamali noted that the fraudsters had invaded the neighbourhoods of South B and South C.
He noted that the operations by the group were costing both the government as well as telecommunication companies a huge chunk of their revenue.
The illegal activity, known as SIM boxing, involves an individual putting up a device that can take up several SIM cards in order to complete voice calls that it receives from internet as Voice over IP.
The system then gives local mobile users the service as local traffic hence undercutting prices charged by the telcos.
Khamali revealed that the system, which could be mounted on rooftops or installed inside the house, caused a lot of interference on both the quality as well as the costs of the network.
“What they do is they sell for you small reduction gadgets. The picocells are installed on rooftops or inside the houses so you find you are on a superior network but yet the people connected to the tower cannot be seen.
“The problem with mobile networks is that of time division. So if the time slots are gone, the other remains idle. So you get the repeaters render a tower useless for the intended plan, by taking over responsibility of distribution,” explained Khamali.
“You find that instead of maybe spending Ksh100 per minute, you go ahead and spend Ksh10, with the SIM box taking Ksh90,” he added.
He further noted that the authority, in conjunction with NIS, had launched a crackdown to flash out the cheats.
This comes barely three months after University of Nairobi (UoN) student was arrested in connection with a new wave of robberies targeting the dead.
In a statement, the Directorate of Criminal Investigations (DCI) indicated that the two individuals identified as Eutycus Muguna Mutembei and Ayugu Eugene Shivachi were charged with stealing Ksh2.8 million from the accounts of a dead person.
In the successful SIM swap scam, the cybercriminals hijack the victimâ€™s cell phone number and use it to gain access to his/her sensitive personal data and bank accounts through the Mobile Banking Apps available on Android and other smartphones.
Once they take control of the swapped SIM card, the crooks insert it in their phone, access the financial accounts and transfer all the funds to other scammed telephone numbers.
Once the cash is withdrawn, they switch off the stolen cards frustrating efforts by detectives to track them down.