KUNMING -- A total of 5,648 suspects have been arrested and more than 11 tonnes of drugs have been seized by police in Southwest China's Yunnan province between January and May, local authorities said Monday.

The amount of drugs seized in the province since 2016 has reached a record high, with the amount of heroin and methamphetamine accounting for more than 80 percent found in the entire country, according to the Public Security Department of Yunnan.

"Yunnan has always been the main focal point of the national anti-drug campaign since it borders the Golden Triangle, an area known for drug production and trafficking," said Guo Bao, deputy head of provincial public security department.

Since the fourth campaign to crack down on drugs started in the province in 2016, police have cleared more than 32,000 drug cases, arrested around 33,000 suspects and seized 61 tonnes of drugs, according to Guo.

In terms of drug rehabilitation, more than 140,000 people have received treatment since 2016 in Yunnan.