Border police in Wenzhou, Zhejiang province have smashed two alleged drug smuggling rings, one of which involved the largest amount of heroin found in the province in the past decade.

The special intercepted 4.16 kilograms of heroin and 5.67 kilograms of methamphetamine and arrested a total of 21 suspects in Wenzhou, Taizhou and Huzhou in Zhejiang province, and Shanwei, Guangdong province, in September.

The drugs were allegedly being smuggled by two different gangs.

“The two cases are both huge cases involving the largest amount of drugs across the provinces in the past ten years,” said Cai Fangxu, senior officer with the border police in Wenzhou.

The first gang of dealers allegedly regularly received packages of drugs from Guangdong province. Local police caught the gang in June. Another gang from the Guangxi Zhuang autonomous region, was caught in August.

The major suspects in the two cases are known to police.