Big names are lined up for the festival

North Wales Police said if under-18s broke the law as they did at last year's festival, it could mean no bars on site in future events.

The festival, which began on Friday night, features stars from the classical, pop, and rock world.

Andrea Bocelli, Van Morrison, Alison Moyet, Katherine Jenkins and festival founder Bryn Terfel are in the line-up.

But police are concerned that under-age drinking could spoil the enjoyment of other festival-goers.

"Last year, children as young as 14 were getting drunk," said Chief Inspector Derek Roberts.

"In co-operation with the organisers, we are going to be clamping down this year.

Andrea Bocelli is following in Jose Carreras' footsteps

"I don't envisage having to take the bars away but, unless things improve, that will be the ultimate sanction."

The Faenol festival was the brainchild of opera star Bryn Terfel and is now in its sixth year. The three-night event features a mixture of opera, rock and pop, show tunes, and Welsh language acts.

Michael Ball, Elaine Paige, and Jose Carreras have all joined the line-up in previous years.

Organisers said 7,000 crowd turned up to watch Katherine Jenkins on Friday night.

Ticket sales are the highest they have ever been, with Sunday night's performance by Andrea Bocelli selling out two weeks ago.

The festival is due to end on Monday evening.

Terfel admitted he had used his own influence to bring in artists of the calibre of Bocelli, Lesley Garrett and Carreras by collaborating with them on concerts and albums in exchange for their attendance at Faenol.

"Without my name, it is very difficult getting these artists," he said.

The singer said he had been surprised by how quickly the festival had become established.