Police officers look at a model of a police helicopter on display at the fourth China (Beijing) International Exhibition and Symposium on Police Equipment and Anti-Terrorism Technology and Equipment on Thursday. Zhang Wei / China Daily

BEIJING - More unmanned aerial vehicles, so-called drones, are likely to be used for security purposes in future, supplementing the anti-terrorism work that currently relies on cars and other ground-based equipment.

Three types of domestically developed unmanned aerial vehicles and one that was imported attracted a lot of attention at the fourth China (Beijing) International Exhibition and Symposium on Police Equipment and Anti-Terrorism Technology and Equipment on Thursday.

"The anti-terrorism concept has evolved. In the past, anti-terrorism efforts depended on things like individual equipment and armored cars. Nowadays, unmanned aerial vehicles and helicopters are more frequently used," said Ma Tenglong, a marketing manager with the Aviation Industry Corporation of China (AVIC).

In anti-terrorism operations outside China - including the recent killing of Osama bin Laden by the United States - unmanned aerial vehicles and helicopters have played an important role in reconnaissance and also carry out air-to-ground attack missions.

"Unmanned aerial vehicles and helicopters will play a bigger role in anti-terrorism missions in the future, both at home and abroad," Ma said.

At present, drones have not been used domestically to strike terrorists, said Li Wei, director of the anti-terrorism research center at the China Institutes of Contemporary International Relations.

"Armed police and other anti-terrorism forces have enough capability to handle terrorists inside the country nowadays," he said. "But unmanned aerial vehicles will be useful for reconnaissance along border areas, where natural conditions are inhospitable, so that terrorists trying to sneak into the country can be found and stopped."

AVIC, the country's largest aircraft manufacturer, displayed three types of drone at the exhibition for the first time.

One of them, named Pterodactyl, can be used for both surveillance and reconnaissance as well as air-to-ground attack missions. It can be used for 20 hours straight and fly at up to 5,000 meters.

Xia Tian, a member of the marketing staff at AVIC's Chengdu Aircraft Design and Research Institute, said the vehicle is "one of the world's most advanced".

The Beijing municipal public security bureau, which co-sponsored the exhibition, told reporters it is considering buying unmanned aerial vehicles for use in emergencies, for the monitoring of traffic and the pursuit of suspects. The bureau said infrared detectors on the drones would be especially useful in locating suspects at night.

The capital now has four helicopters and a number of small reconnaissance drones. Because the city's airspace is under strict air traffic control, unmanned aerial vehicles also have the advantage of being subject to less air traffic control than helicopters, Jia Wensheng, a bureau official, was quoted as saying.

In addition to aircraft, more than 200 exhibitors displayed other anti-terrorism technology and equipment at the exhibition, including a fast detector of liquid explosives and face-recognition technology.

Li Wei said face-recognition technology could have a broad application in China because it can work with widely installed security cameras and would help with the locating of wanted terrorists and suspects.