The National Bureau of Investigation (NBI) said Wednesday that hackers involved in the defacing of government agencies’ websites could have used proxy servers to avoid detection as two government agencies have already submitted the logs in a bid to trace the culprits.

Head Agent Palmer Mallari, chief of the NBI Anti-Computer Crimes (ACCD), said the Technical Education and Skills Development Authority (TESDA) and the Department of Social Welfare and Development (DSWD) have submitted the logs to the bureau.

However, the hackers who defaced the website of the Department of Health (DoH) had removed the logs in apparent efforts to prevent the bureau from tracing them.

Palmer said the National Disaster Coordinating Council (NDCC) and the Department of Labor and Employment (DoLE) have yet to file formal complaint to the bureau.

The NBI-ACCD chief said they considered this case more difficult because they are dealing with individuals who are experts in computer.

“The hackers are experts. It is also possible that they used proxy servers. For all we know the hackers are just here in the Philippines but since they are using proxy servers, they can make it appear that they are in China,” he said.

Palmer also said that they consider this case as more difficult as compared to that of the Katrina Halili-Dr. Hayden Kho sex video.

“This is more difficult because we are dealing with hackers who could be experts IT. In Katrina Halili case, the source of the sex video had just used an email with attachment. It happened that he/she used Gmail and we cannot see the IP address so we have to wait from the response of the Gmail to give us the IP address,” Palmer said.

Palmer earlier said white hat hackers are one of the angles being pursued in the investigation of incidents of defacing of government agencies’ websites. “The angle of white hat hackers remains. But we are not only focus on white hat hackers but as well as other angles that include political, economic and commercial,” he said.

Palmer said they are not also ruling out inside job. “They have the so-called white hat hackers who are computer security experts. They are expert in penetration testing, to ensure that a company's information systems are secure. They are so good in testing methodologies,” Mallari said.