Police have issued an urgent warning after five people needed hospital treatment after taking illegal drugs.
Police believe the young people, all from the Colburn area, sought hospital treatment at the weekend after taking LSD.
Enquiries are ongoing to identify the source and supply of the drug, which is in the form of small black paper squares with a red flash design.
Richmondshire police say they are extremely concerned that others may have taken, or are going to take, it.
Inspector Mark Gee, of Richmondshire Neighbourhood Policing Team, said: “Our message is clear: these drugs are inherently dangerous, particularly when taken with other substances including alcohol.
“It is illegal and could have serious consequences.
“If you or anyone you are with have taken illicit substances and become unwell, please seek appropriate medical attention as soon as possible.
“Illegal drugs often contain different substances, making it impossible to visually identify what they are, or how strong they are
“The effects of this hallucinogenic can be strong, unpredictable and overwhelming to the user, as seen with the hospitalisation this week of a number of young people locally.”
Anyone with information about these drugs is asked to contact North Yorkshire Police on 101 quoting reference number 12210064362, or contact Crimestoppers anonymously on 0800 555 111.