China says its domestic Internet security is under threat, blaming cyberattacks originating outside the country. The National Computer Network Emergency Response Technical Team warned online attacks on domestic networks have grown sharply this year, the China Daily reported Monday. The agency was quoted as saying about 7.8 million computers were affected in 27,900 attacks that originated outside China, between January and June. The agency said the United States hosted many of the overseas command and control servers used in the attacks with 24.2 percent, followed by Japan with 17.2 percent and South Korea with 11.4 percent. \"Online attacks against our country are coming from outside our borders and the situation is growing more serious,\" Zhou Yonglin, the team\'s administration and operation director, told China Daily in an interview. He said hackers used IP addresses and servers overseas to infect networks with Trojan viruses and create collections of compromised devices. The report said in April hackers allegedly from the Philippines defaced several Chinese websites and left insulting messages relating to an island dispute between the two countries. It said another hacker group threatened in June to infiltrate government, education and medical websites in China. Zhou said while there were threats from abroad, it also was possible \"that someone in China could control an IP address or server overseas to launch an online attack on Chinese websites and computers\" as many Chinese websites lack the capability to repel such attacks. \"International cooperation is essential to halt attacks and enhance security for everyone on the Internet,\" Zhou said.