Police have found that a number of prisoners at Preston police station has previously taken these tablets and were subsequently taken to hospital suffering from a number of side effects.

These include discolouration of the skin, violence and aggression or falling asleep.

Detective Inspector Dave McKenna, from Preston CID, said: "Our intelligence is that there are many thousands of these fake Valium tablets in circulation.

"People who have taken these tablets have suffered serious side effects and often require hospital treatment.

"The police are working with partners and drug agencies to spread the message that these tablets are a serious health risk.

"I would urge anyone offered or in possession of a suspected fake blue Valium tablet not to take it, but destroy it or hand it into the police.

"I would ask members of the community if they have information regarding who is supplying these tablets to contact the police."

Anyone with information can call police on 01772 203203 or Crimestoppers on 0800 555111.

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