BRADFORD coroner Martin Fleming has ruled every drugs death in his jurisdiction must now be routinely tested for two destructive substances claiming lives.

Mr Fleming instructed toxicologists to start carrying out the tests following police concerns about an increasing number of drugs deaths in the district linked to the supply of potentially deadly substances being brought in from China and Hong Kong.

A senior detective in West Yorkshire, who is in charge of investigations surrounding the supply of the drugs to the district, warned earlier this month users were playing "Russian Roulette" with their lives.

And this week Mr Fleming pledged his support for the police investigations which revealed four deaths in Bradford were being linked to Fentanyl which is mixed with heroin but is considerably stronger.

Pure Fentanyl is 50 times stronger than heroin and 100 times stronger than morphine but there is also concern about the increase in the use of Carfentanil, an illicit version of it, which has been linked to deaths in the US and which is 10,000 times stronger than morphine.

Fentanyls are taken either directly or mixed with low grade heroin and users are potentially miscalculating the amount to use and are dying because of the effects.

Currently, 73 deaths are being investigated and a further 50 have been positively linked to the substance with 16 in West Yorkshire.

Mr Fleming said he "wholly supported" the police investigations although it was driven by a different motive to his routine testing.

"The police's motive is a criminal investigation. It's an investigation that's invaluable but I'm looking at it as a cause of death. It's in the public interest to look very carefully at a drugs death to see if these two drugs play a part," he said.

Historically there have been three known Fentanyl deaths in Kirklees with no suggestion of Carfentanil and one Fentanyl death in the Bradford area.

"It's a worrying problem nationally. It's something we are keeping a close watch on in this area, said Mr Fleming.

Any findings of Fentanyl/Carfentanil from the routine tests will be passed on to police for their information.

"This is an early doors inquiry. It's not the case that we have uncovered an epidemic in this area but it's not to say that it isn't reality. The police will be made aware of any findings. It's a case of being alert," he added.

Fentanyl can be prescribed as a top-shelf painkiller for chronic conditions.

"Taking any drugs from the streets is really rolling the dice. You don't know what contaminants are in it that could kill you and you don't know the potency. It could be any drug but Carfentanil is especially potent and especially fatal. People who acquire it might not be aware of its potency. The message is you don't touch the stuff."

Detective Superintendent Patrick Twiggs previously told a press conference that Fentanyl was being bought on the dark web from China and Hong Kong, though it was known to be available from Mexico and Canada as well. Its use is limited to drug users so there is no general threat to the general public.

"Why they are risking it? I do not know. My advice to drug users is don't touch it because then you are playing Russian Roulette," he said.