HANGZHOU -- Over 100 suspects have been detained while more than 50 kilograms of drugs seized in a major drug trafficking case, local police in East China's Zhejiang province said Wednesday.

Police in Cangnan county of the province received information about a large drug trafficking network in Feb 2015 and launched an investigation team.

One of the prime suspects was arrested by police in Pingyang county in July 2015. Around 13 kilograms of methamphetamine were found at the scene.

Another 15 kilograms of methamphetamine were seized at the house of another prime suspect and he was also arrested.

The drug trafficking network had expanded to provinces of Hubei, Fujian and Yunnan. The investigation team spent three years locating the other suspects involved.

Over 30 kilograms of methamphetamine and other drugs including heroin and methadone, as well as more than 1.2 million yuan ($185,000) were seized.

Eight people have already been sentenced to the death penalty. Further investigation is under way.