Police from North China's Shanxi Province have busted a drug plant hidden inside an abandoned petrol station, seizing three suspects and 2.1 tonnes of raw materials for making drugs.

In January, police from Taiyuan, capital of Shanxi, got information about a drug gang and found a suspicious deserted gas station in Loufan County. They launched raids in late March.

Investigation showed that the three suspects illegally purchased large quantities of ephedra herbs, which is a major material for producing the methamphetamine, or "ice," from north China's Inner Mongolia Autonomous Region and made drugs in Shanxi.

Many drug manufacturing equipment and around 278 grams of methamphetamines, 2.1 tonnes of solid raw materials, and 45 tonnes of residual solvents in the manufacture of drug substances were seized on the site.

China has taken a tough stance and stepped up efforts to crack down on drug crime.

Shanxi public security authorities said Tuesday that local police had seized more than 2.5 tonnes of drugs since a three-year anti-drug campaign was launched in May 2018.

A total of 2,548 suspects were caught in 2,052 drug-related criminal cases over the past year.