Intruders broke into the Mountbatten Centre at some time over the weekend and cut off the electricity supply.

The centre, off Twyford Avenue, Stamshaw, was forced to close for the day because staff were unable to work the lights and equipment.

The vandals broke in to the building after cutting the power and stole wiring and metal.

Police received a call at 6.15am after staff discovered the break-in.

It was not known today when the centre would be able to re-open.

City council spokeswoman Stephanie Light said: 'It's closed until further notice.'

The incident is being treat-ed as a burglary and is under investigation by the police.

Safety engineers were this morning on the site trying to fix the problem in the hope of getting the centre re-opened.

One regular visitor to the centre, said: 'I went to go to the gym there at half six this morning and they (the staff) said the centre would not be opening because last night vandals had cut through the electricity.

'I was very annoyed getting up so early to go and do my usual workout as I could have had an extra hour in bed.'

Portsmouth South MP and city councillor Mike Hancock condemned the burglars.

'I think it's terrible,' he said.

'I don't know how vandals could have got into there and why they did it.'

The centre, which is under re-development, has just celebrated its 25th birthday.

The health and fitness club is a popular feature of the city, with regular visitors using the leisure facilities.