Police have stepped up patrols following reports of needle spiking in nightclubs in Bangor, north Wales.
Uniformed and non-uniformed police officers will now circulate the area in a bid to tackle the problem.
North Wales Police said nightclubs in the area are also cooperating with them to ensure the safety of their customers.
Needle spiking is when an offender injects an unsuspecting person with a substance using a needle.
The charity Victim Support says around three quarters of spiking victims are women, but men can be targeted too.
Last year, reports of people being spiked by injection increased with individuals giving accounts of being pierced by a needle in their legs, hands and back.
North Wales Police is urging club-goers to report any suspicious behaviour to them in the first instance.
The force said it had been made aware of victims disclosing suspected spiking on social media before they made a formal police report.