Sierra Leone Information and Communication Minister Alhaji Ibrahim Ben Kargbo called on mobile-phone companies to register subscribers' SIM (Subscriber Identity Module) cards at a press briefing last week.

Mobile-phone users have encountered threats and intimidation, and the perpetrators have taken advantage of anonymity, Kargbo said.

"It is difficult to trace those who are engaged in such dubious habits simply because the phone companies cannot even trace those involved in such dubious acts, let alone the police," he explained.

SIM card registration, according to Kargbo, would aid in police investigations, record-keeping, reconciliation and deterring criminal activity perpetrated via mobile phone.

Some telecom market observers believe that Kargbo's comments could lead the National Telecommunications Commission to invoke existing regulations to mandate the registration of SIM cards in the near future.