THREE hundred teenagers were found at an all-night rave inside a huge warehouse in Blackburn.

Officers said the youths, aged 14 to 16, were also smoking shisha tobacco at the former furniture unit in Weir Street off Darwen Street in the town centre.

Word of the warehouse spread by word of mouth on social networking sites, police said.

But town centre officers, fire chiefs and council investigators crashed a party on the back of an anonymous tip-off.

Inside they were shocked to find 300 youths, evidence of under-age drinking, DJ decks and a ‘large-scale’ shisha den.

The warehouse has now been closed down on health and safety grounds.

A council boss said the raid showed the problem with children smoking shisha illegally in the town was far worse than had been feared.

The scruffy-looking unit, accessed through blacked out doors, is the former Burn Side Furniture Complex in Burn Side Mill and is meant to hold no more than 60 people, police said.

It is owned by a London-based company and police said it was being sub let to a person who charged teenagers £2 a head to get in.

Officers are continuing to investigate who is behind the promotion, but say they have had assurances that it will not re-open following their raid.

Police Sergeant Steve Finley reported incidents of ‘overcrowding, disorder and unlicensed shisha smoking’ at the rave.

Sgt Finley said: “We ended up escorting 300 people off the premises for their own safety.

“There were a number of incidents we had concerns about such as fire risks, no entertainment licence and under-age drinking.

“This was an organised party. There had been a number of them at this place, but this was the big one thanks to the wonders of Facebook.”

Police said schoolchildren had come to the illegal party from Blackburn, Darwen, Hyndburn and the Ribble Valley.

Sgt Finley added: “We don’t want to stop kids enjoying themselves, but if they are paying to get in these venues, they need to make sure they are licenced and within the law.”

The events are advertised on Facebook as ‘Passion’ or ‘Xsquared’ and call themselves a ‘new and improved shisha place in Blackburn’.

The site says: “Unwind and experience the taste of exotic eastern hookah in our dedicated Shisha Café “XSquared”. We deliver the best shishas using only authentic Al-Fakher and Starbuzz flavours, all kinds of drinks, ice cream and milkshakes are also available.

“We cater for large groups up to 300 people so feel free to ask if you are interested in making a booking. The only Shisha place in Blackburn to have such a fantastic atmosphere so come down and enjoy a Shisha while watching your favourite programs on a big screen.”

A message on the same Facebook page now says the shisha and dance venue, which opened from midday until 3am at weekends, is closed. But it adds: “We'll be back don't worry people. Keep tabs on this page especially after exams, we'll be opening soon with a brand new name and image.”

When the Lancashire Telegraph rang the number advertised on the web page a man answered and claimed not to be involved in the venture.

A Telegraph investigation previously revealed that dozens of under-age youngsters have been sneaking into rooms above properties in Darwen Street for shisha smoking sessions.

Coun Maureen Bateson, executive member for children's services, said it was worrying that the problem may be bigger than was previously thought.

She said: “Somebody is making a profit out of these young people without thinking about the risks.

“I will be raising this issue at the safeguarding board on Monday. We've seen small groups up to now, but this is something much more worrying.”

Shisha cafes can be licensed but they must adhere to strict health and safety guidelines, as well as smoking legislation, including only selling products to adults and not allowing smoking 'inside'.

They must also prove they have paid duty on the tobacco to Revenue and Customs..

A shisha pipe, also known as a hubble-bubble pipe, is a single or multi-stemmed instrument for smoking tobacco in which the smoke is cooled and filtered by passing through water.