The justice ministry is to tighten the ban on more than 100 chemicals used in the production of illegal drugs such as speed, crystal meth and XTC from the end of this week.

At the moment prosecutors must prove that people caught in possession of banned ingredients, such as BMK and PMK, were aware they could be used to manufacture synthetic drugs.

Justice minister Dilan Yesilgöz said that an absolute ban on possession would close a loophole and help the fight against gang-related violence.

Drugs laboratories are often located on farmland and in locations where owners can plausibly deny that they were storing chemicals for purposes unconnected with drug production.

‘Owners of sheds and storage facilities often come under pressure to set up drugs labs, our environment is being seriously polluted by the dumping of chemical waste and assassinations take place in the streets,’ Yesilgöz said.

The ministry has revised its list of banned substances after consulting police, experts in chemistry and the national forensic institute. The list comprises chemicals that are known to be used in the production of synthetic drugs and have no legal application.