Jun 14, 2011 16:53 GMT  ·  By

Hackers have taken up a role in the South China Sea territorial dispute between Vietnam and China and hundreds of websites were compromised on both sides.

Ever since a confrontation between a Vietnamese ship and Chinese patrol boats occurred last month in disputed waters, tensions between Hanoi and Beijing have increased.

Protests were held in Hanoi and Ho Chi Minh calling on the government to protect the country's territorial waters which are subject to a long dispute with China.

Hackers on both sides have attacked and defaced official government websites. Chinese attackers left their country's flag on compromised Vietnamese websites, while Vietnamese hackers posted images of armed men on Chinese sites.

The attacks have intensified even more since Vietnam held live-fire drills in the South China Sea yesterday. The disputed waters are not only part of important shipping routes, but the land beneath them is known to contain important oil and gas deposits.

The VIETNAMNET news website reports that over 1,500 Vietnamese websites were affected by Chinese hackers during the last few days. Apparently many of them were hijacked when an important DNS server was compromised.

Vo Do Thang, director of the Athena Network Security Center said that DNS attacks are very serious because they allow hackers to redirect users to other servers.

He advised all Internet service providers in the country to be on high alert against such attacks. Indeed, hackers could redirect Internet users who rely on the compromised DNS server to malicious websites that spread malware or exploits.

Chinese hackers are known to attack the websites of other governments during political tensions. Last year, Japan accused Chinese hackers of launching distributed denial-of-service attacks against several of its official sites.

The attacks accompanied a similar territorial dispute that resulted from a Chinese trawler colliding with two Japanese Coast Guard boats in waters surrounding the Diaoyu islands.

The small islands, situated 120 nautical miles northeast of Taiwan, were assigned to Japan through the Treaty of San Francisco, but China does not recognize this and claims they are part of its territory since ancient times.