Airtel will expand its network reach to 730 towns in Karnataka by the end of this financial year. It plans to set up 600 additional cell sites across the state taking the count to over 1,800 by March 2006. Company officials said that Bharti is planning to invest about Rs 3.8 billion for the same in 2005-06. According to reports, the aim is to reach out to 45 per cent of the population. The company has already crossed its customer base of 1.5 million in Bangalore.