Airtel Sierra Leone, the local mobile unit of Indian telecoms group Bharti Airtel, has expanded coverage of its wireless network to the entire Tonkolili district, in the Northern Province of Sierra Leone, allAfrica.com reports, citing local newspaper Concorde Times. The move forms part of the operator’s rural expansion drive; earlier this year Airtel brought mobile services to Sahn Malen in the Pujehun District in the south of the country. According to TeleGeography’s GlobalComms Database, Airtel (then known as Celtel) launched GSM-900 services in Sierra Leone in April 2000. The company adopted the Zain brand in August 2008, ahead of another rebranding to Airtel in late 2010, after Bharti Airtel finalised the acquisition of the African assets of Zain Group in June that year. The company took over Zain’s operations in 15 countries, including Sierra Leone, Malawi, Burkina Faso, Ghana, Kenya, Nigeria and Uganda.