The number of cyber attacks on New Zealand computers has almost doubled in the past year, the Government agency in charge of internet security says. It comes as an international report says the country is at a greater risk of being cut off entirely from the internet than many other nations around the world. "We're seeing a lot more activity generally around the world in this space," said TUANZ chief executive, Paul Brislen . The United States has also pointed the finger at the Chinese military for concerted attacks on American companies, US government agencies and vital infrastructure.In the past two weeks 75,000 people were forced to change their Yahoo-Xtra passwords after hackers broke into the email provider and issued a widespread spam attack. The National Cyber Security Centre, which is part of intelligence agency the GCSB and is tasked with keeping New Zealand's critical infrastructure safe, says New Zealanders need to be aware of such attacks. "We...