The public face of one of the country’s most secretive groups says “rogue insiders” could pose a risk to Australian internet security.

Steve Meekin, the deputy secretary of intelligence and security, oversees the Australian Signals Directorate – our equivalent of the United States’ National Security Agency (NSA). Mr Meekin says one of the biggest risks to Australian security is not the rampant and unchecked probing of private networks by the United States, but the possibility that someone may reveal such behaviour, as CIA employee Edward Snowden has done.

Mr Meekin also warned the threat of cyber crime is increasing rapidly, the number of cyber security incidents identified by or reported to the Cyber Security Operations Centre was 1,259 in 2011 and 1,790 in 2012, there were 789 incidents between January and May this year.

Mr Meekin said the threat of cyber attacks comes from a range of sources including "individuals, activists and organised criminal groups", with allegedly more than 80 per cent coming from foreign states and 65 per cent of cyber intrusions having an economic focus.