The unannounced calls at licensed premises in the Wrexham North area, which includes Gwersyllt, Coedpoeth and Gresford, on Friday and Saturday evening were part of a special operation carried out by officers working under district Inspector Alex Goss.

Molly, the police's black labrador sniffer dog, and her handler, did not find any traces of illegal substances and there were no arrests or cautions.

"We picked on pubs, visited them and spoke to the licensees to make sure everything was in order," said Inspector Goss.

"We let the drugs dog Molly have a walk around and go to the public areas like the toilets and beer gardens.

"It was for the reassurance of licensees, supporting them and enforcing the law.

"To be fair everyone was very well behaved – there were no arrests or cautions and everything was in order.

"We will be doing it again and visiting other pubs in the Wrexham area. We will visit them at random without prior warning to support the licensees and we do these checks in conjunction with Pub Watch."

The Pub Watch initiative sees police meet licensees in the Wrexham North area every month.

"We tell licensees at the Pub Watch meetings that we can visit pubs at any time we want with the drugs dog, but we don't tell people where we're going," explained Inspector Goss.

"Sometimes they will ask if we can take the dog to their pub at some point – not because there's anything happening but for reassurance – and we say we will do, but we can't give them any warning."