Bosses of a music festival which attracts thousands of people to Sussex have been ordered to stick to nearly 100 strict conditions.

Organisers of the Beachdown Festival have been told to improve security and ensure that live music stops at 11pm after police raised a series of concerns.

Up to 10,000 revellers will be banned from taking alcohol into the site while bar staff will ask for ID from anyone they believe to be under 25.

The 95 conditions were imposed on Beachdown, which is held over the August bank holiday at Devil's Dyke, after licencing meetings with Mid Sussex District Council.

Festival bosses said the conditions were not unusual and the event would go ahead as planned.

But Jean Irving, Sussex Police’s licensing and public safety manager, warned that officers would not hesitate to close the event following a number of incidents last year.

She said: “The police will not shrink from closing it down before it even gets started if public safety or any of these things are compromised."

Sussex police said the conditions are required after last year's festival because organisers had not finished constructing the arena by the time festival-goers started arriving, meaning environmental health officers could not inspect and sign the safety certificate.

Meanwhile about 4,000 people jumped over the fence to gain entry, meaning 50% more people were at the festival than was predicted.

As a result conditions imposed on organisers this year include more security at entry points, the site being reduced by a third, a £50,800 bill for policing, to be paid six weeks in advance and one in 20 people to be searched on entry.

Acts this year include Grace Jones, The Zutons and Super Furry Animals.

Organiser Joe Pidgeon was not phased by the development.

He told The Argus: "We are as concerned with health and safety as the police.

"The fencing at this year's festival will be a solid shield field rather than the wire fencing we had last year.

"It's true the site wasn't complete by the time people started arriving, but we were dealing with horrific weather conditions and this year we have given ourselves an extra week to set up.

"There will be a dedicated 10,000 gallon tanker of water for the fire brigade and we have also spent £10,000 on a private fire brigade as we did last year.

"There are lots of positive changes for Beachdown 2009 - the site of the performance field has been reduced but the camping area is bigger and although we have an 11pm cut off for live music we have two extra hours or non live music and bar licences which will go on until 4am."

For more information about the event, which is held between August 28 and 31 and to buy tickets, go to www.beachdownfestival.com