Police laid in wait in thick grass for more than 30 hours before raiding a drug lab in a forested area of Ruyuan county, Guangdong province.

"We had to climb over wild thorns and cross barriers set up by the suspects during the operation," said Ouyang Zhifang, director of the drug enforcement detachment of the Shaoguan city bureau of public security.

"Police seized 313 kilograms of methamphetamine, commonly known as 'ice', 76 kilograms of semifinished ice, plus plenty of equipment for producing the drug," Ouyang told a news conference on Monday.

Eight suspected drug gang members, including two suspected heads surnamed Cao and Li, were detained during the Nov 28 operation involving more than 500 officers.

The gang had occupied an area surrounded by forested mountains on four sides, Ouyang said.

"They built several single-story houses and equipped them with air-conditioning facilities and bought fridges, big plastic buckets and rubber gloves," he said.

The secret base, near Aotou village, was more than 15 kilometers from downtown and the suspects used a van to transport materials and drugs along a winding, mountainous road, Ouyang said.

"The crackdown on a major drug case has dealt a heavy blow to local drug traffickers and producers," he added.

A police officer with the Guangdong provincial department of public security reiterated that fighting drugs and drug-related crimes is a long-term and difficult task in Guangdong, which has the country's largest number of drug addicts.

He hinted that more campaigns will be launched.

Guangdong has been the focus of China's anti-drug campaign for many years, the officer said.

The ice produced in Guangdong represents more than 50 percent the mainland's total, while ketamine reaches one-third of the country's users, according to official statistics.

Earlier this year, police busted a major international drug-trafficking channel following a crackdown on a major drug gang headed by a Taiwan resident in Yangjiang, western Guangdong.

The gang smuggled ice and ketamine produced in Guangdong to the rest of the world via the drug trafficking channel.

Police seized 1.39 metric tons of liquid ketamine, 24.6 kilograms of finished ketamine and three tons of supplementary materials after raiding three drug production locations.

A total of 27 suspects, including a suspected gang head surnamed Chen and a key gang member surnamed Wang, were detained.

Both Chen and Wang are Taiwan residents.