A SWIMMING complex was closed today after vandals caused thousands of pounds worth of damage and left the pool full of broken glass.

Hundreds of swimmers were turned away from Waves Water Fun Centre in Nab Lane, Blackburn, after a fire extinguisher was hurled through a two metre by one metre window.

One other window was badly cracked during the attack, which left shards of glass in the pool and on the poolside.

The pool was half drained and then staff wearing snorkel equipment searched the bottom for glass, before the centre's mechanical vacuum was used to make sure all shards were removed.

Each of the two damaged windows will cost £1,500 each to replace because of the special curved glass used as part of the building's design.

CCTV footage shows three males outside the centre shortly after 10pm on Tuesday.

One of them armed with a fire extinguisher sprays the others with jets of water, before attempting to throw it through a window a few metres from the entrance.

When that fails, the youths launch the extinguisher through a second window.

Waves manager Pat Campbell said: "We get targeted by vandals quite a lot because of the building's glass walls - I've been here just over a year and this is about the fourth incident, but it's the worst yet.

"It's not just the window replacement cost this time.

"It's still school holidays for areas outside of Blackburn, and we get a lot of custom from outside the area, so we were expecting hundreds of customers.

"We've currently got an extended lunchtime swim, as well as the regular sessions of mother and baby swim, and a session for the disabled, all of which have had to be cancelled."

As well as an estimated £1,000 through lost takings, the Blackburn with Darwen Council-run centre has had to cover the cost of employing extra staff for the extended sessions and school holiday programme, only for them to be left with nothing to do.

Mr Campbell said: "This is not something we can claim for on insurance because of the excess, it will have to come out of our budget."

Draining the entire pool completely would have added to the centre's costs, which will already hit around £5,000.

It opened again this evening.

Steve Rigby, the council's director of culture, leisure and sport, said: "We are furious about this mindless act of vandalism that has prevented people using the full facilities at Waves.

"However we have CCTV footage and we are working closely with the police to try to track down the perpetrators."