The torches show up even small traces of cocaine as bright green
Ultra-violet light is being used by Cumbria Police as the latest weapon in the battle against illegal drugs use.
Police have distributed ten "cocaine torches" to neighbourhood policing teams and drug squads in the west of the county.
Shone on noses and mouths, they show minute traces of cocaine which might be invisible to the naked eye.
Anyone suspected of using the drug will be searched by officers and prosecuted if necessary.
Supt Andy Towler, said: "The equipment looks just like a normal LED torch, but if it is pointed at a person's nose and mouth area it shows up bright green if they have been using cocaine.
"It is even easy to see the minute cocaine crystals secreted within the nasal hair.
"Small traces of cocaine are also left on the cheeks and chin that are not visible to the naked eye and these show up bright green too under the torchlight."
He added: "Not only will it make it easier for police to identify possible offenders, but it will also act as a significant deterrent to those intent on using the drug, especially in our pubs and clubs."