Doors and windows were smashed and furniture wrecked in the assault on the property, a listed building on London Road, which is also home to the London Road Pre-School.

Ana Alves, a scout leader, said they had an event at the hall on Saturday night and when they returned on Sunday to clear up they discovered it had been broken into.

'It looks like they had tried to get in through the back door but could not so broke a kitchen window and came in there,' she said.

'They destroyed everything, doors, windows, cupboards, anything that was closed was opened, but nothing was taken.'

Police were called and experts dusted the building for fingerprints. A clean up operation has also taken place but quotes are being sought for some of the more major repairs which could cost several hundred pounds.

Mrs Alves said although they could put the building back together the emotional effects on the scouts would be long-lasting.

'We have about 80 scouts and beavers aged between six and 14 and they all work really hard on the building to fix it up and make it look nice,' she said.

'They now feel all their hard work is for nothing. The younger ones are quite scared and don't understand why someone would do this. We want them to feel safe here.

'As it is a listed building we will have to get approval to replace doors and windows.

'We just feel so angry.'

Group scout leader Caroline Ellis said the building was over 100 years old and all its fittings were non-standard sizes. 'You can't just buy a new window off the shelf,' she said.

'The upkeep of these premises is huge as it is and we had just agreed to try and raise £70,000 to £80,000 to repair the roof so this means we have to completely rethink our plans and look at installing more security measures.'

Pre-school supervisor Resette Coppack said they had been able to do some repairs to enable them to open for children on Tuesday morning.

'They crowbarred a filing cabinet so we are having to replace that and my husband has spent a day fixing a fire door,' she said. 'Just this afternoon we noticed the letter box that was screwed to the wall outside was gone so we presume they took that.'

The pre-school is holding a fund-raising Reading Cafe at the Scout Hall on Wednesday, March 9 at 9am. Parents can enjoy a bacon sandwich and a story and fun activities with their children.

Anyone with information about the break-in should call Norfolk police on 101 and quote reference number 36/16709/16.