The email system of a university in Northwest China's Shaanxi Province - well-known for its aviation, aerospace and navigation studies - was recently attacked by an overseas hacker group, the university said, and a case has been filed with the police for further investigation.

Hackers and criminals from abroad were caught sending phishing emails with Trojan horse programs to teachers and students at the university, attempting to steal their data and personal information, Northwestern Polytechnical University said in a statement on Wednesday.

Cybersecurity analysts told the Global Times that attacking a university that is of great importance for its research and study of aviation, aerospace and navigation by foreign hacker groups was only the tip of the iceberg of hacking by overseas forces, as those key industries linked to China's security had frequently been targeted over the years. 

The rising defense capability of the university prevented data leakage this time, but it was a warning to Chinese institutes to further raise their alert in the face of deliberate hacking, especially anti-China forces.  

The police report did not reveal in what country the hackers were based. But for a long time, some groups such as the US National Security Agency (NSA) have launched large-scale network attacks around the world for the purpose of intelligence collection, with China being one of the main victims.

To determine further facts, the university said that it had reported the case to public security organs.

According to a police statement released by the Beilin Public Security Bureau in Xi'an on Thursday, a police station in Xi'an Taibai Road received the report on April 12 at about 3 pm. The attack attempted to lure teachers and students into clicking links of phishing emails with Trojan horse programs, with themes involving scientific evaluation, thesis defense and information on foreign travel, so as to obtain their email login details.

The police statement said that "the cyberattack posed great security threats to the information system of the university and key data of teachers and students."

Evidence has been obtained and the Beilin Public Security Bureau has filed a case in accordance with article 285 of the Criminal Law. The initial technical evaluation showed the attack was launched by hackers from overseas.

The Xi'an-based Northwestern Polytechnical University is known for its studies and research into aviation, aerospace and navigation. It is funded by the Ministry of Industry and Information Technology. 

The US government has long seen the university as a thorn in its side, and it has put it on a blacklist of sanctions, accusing it of threatening US national security.

The attack has so far led to no leakage of key data, but it still shows a huge risk, the university said. 

Qin An, head of the Beijing-based Institute of China Cyberspace Strategy, told the Global Times on Thursday that the successful defense against cyberattacks by the university illustrated its rising awareness of cybersecurity and capacity to defend against cyberattacks, as the country maps out measures to address attacks by foreign forces that have been deliberately targeting China for years.  

The university said that it has been paying great attention to cyberattacks, with the application of regular cybersecurity inspections and technical monitoring, as well as increased sensitivity among teachers and students to cybersecurity.

The university reserves the right to take legal action, and will take measures to build a strong network security barrier as well as safeguard the legitimate rights and interests of teachers and students, it said.

Qin said the attack was not a chance event, rather, it was only the tip of the iceberg of wide attacks against China. Those attacks tend to be more complicated in their methods and more targeted, especially on the country's many fields that involve national security.

Over the years, China has been a major victim of cyberattacks. Data obtained by the Global Times from security companies revealed details of more than 2,700 advanced cyberattacks by at least 40 high-level overseas hacker organizations against China in the past few years, aimed at industries, governments, universities and medical institutions.

A report that the Global Times previously obtained from the National Computer Virus Emergency Response Center revealed that China captured a spy tool deployed by the US' NSA, which is capable of lurking in a victim's computer to access sensitive information and was found to have controlled global internet equipment and stolen large amounts of users' information.

The police reminded the public that cybersecurity is not a small issue. Individuals and organizations have the right to report cases to the police in accordance with the country's cybersecurity law. The public security organs will severely crack down on illegal behavior.