Counterterrorism work between China and the United States has helped authorities track down and delete a number of violent, terrorist video and audio programs stored on US servers, a senior official from the Ministry of Public Security said.
"We have agreed on enhancing judicial cooperation on fighting terrorism, especially cracking down on violent and terrorist audio and video files released online in the US," said Yang Shaowen, deputy director of the ministry's International Cooperation Bureau.
The situation has worsened across the country this year, as the East Turkistan Islamic Movement and other groups have released more materials promoting terrorism on overseas websites, the State Internet Information Office said.
The number of investigated terrorism-related videos has risen from 13 in 2011 to 109 last year, the State Internet Information Office said.
Yang said many Xinjiang terrorist suspects and other religious extremists "watched violent and terrorist videos, and listened to audio materials on the Internet, before they conducted brutal terror attacks".
Those include knife-wielding assailants killing 29 people in Kunming, Yunnan province, on March 1, and a bomb attack that killed 43 in Urumqi, capital of the Xinjiang Uygur autonomous region, on May 22, according to Yang.
In addition, due to the spread of online religious extremism, many young Xinjiang extremists have illegally crossed China's borders to countries such as Syria and Iraq to join local extreme Islamic forces, he said.
After receiving special armed training, some terrorist suspects return to China to plan more brutal terrorist activities, according to Yang.
Since January, the ministry has held many rounds of talks with the FBI and US Ministry of Justice to exchange views on investigating the illegal websites and getting rid of violent and terrorist content on the Internet, he said.
"US judicial organs have been adopting an active attitude to support our requests and assist us to investigate and remove many such files from the websites based in the US," Yang said.
Moreover, China has enhanced law enforcement cooperation with the US and a number of Southeast Asian and Middle Eastern countries, and it will conduct joint operations when appropriate to combat terrorism.
Yang acknowledged that because the suspects continually change website registrations and addresses, and use fake identities, it is difficult for police to capture them.
"Recently, the Internet has become one of the main channels for Xinjiang terrorists and other religious extremists to collect funds, recruit, build connections, and plan and organise terror attacks," said Mei Jianming, director of the Anti-Terrorism Research Center at the People's Public Security University of China.
He said that the US has technological advantages that allow it to efficiently locate the illegal websites' terminals.
"The two sides should enhance judicial cooperation with a view to intelligence sharing, technology research and development, as well as personnel training," he said.