NATO logged a 60-per-cent increase in cyberattacks in 2016 compared to the previous year, the organization said on Thursday, noting that its experts responded to roughly 500 incidents each month last year.
NATO spokeswoman Oana Lungescu said that foreign governments, criminals and terrorists can all be behind attacks on NATO's networks without specifying any country or entity.
"Nations have the largest resources in the cyber field – and they are responsible for the majority of targeted attacks against NATO networks," she said.
Besides incidents requiring a response from NATO's 200-member cyber-security team, the organization logs 500 million "suspicious cyber events" daily, which are dealt with through an automated system.
It is unclear if hackers have been able to inflict major damage on NATO or steal classified data. According to NATO officials, hackers have temporarily disrupted NATO websites in the past.