Most people would jump at the chance to have a multimillion pound six-lane swimming pool, gym and sports hall to themselves.But for three women an opportunity to have free reign inside the £8.

Most people would jump at the chance to have a multimillion pound six-lane swimming pool, gym and sports hall to themselves.

But for three women an opportunity to have free reign inside the £8.9m Dereham Leisure Centre was not quite so inviting.

Davina Cannon, 28, and her two friends, were still getting changed after a late night swim session at the centre when they found themselves plunged into darkness and heard the locks snap shut.

Miss Cannon, who was with her friends, factory administrator Demelza Clark, 26, and secretary Samantha Peters, 21, said they hurriedly dressed in the blackness and Miss Peters ran to the front desk to find an empty building.

“We checked all the doors and everywhere was locked. I was really shocked and a bit angry,” said Miss Cannon.

Working in the gloom the trio used managed to contact the police and Breckland Council but neither could raise the key-holders, leaving the women wondering if they were going to be trapped in the building all night.

It was not until just after 11pm that police told them they could leave the building using the fire doors.

“I am extremely disappointed in the staff and the running of Dereham leisure pool and cannot understand why no-one had entered the changing rooms to check it was empty. Three girls chatting and making noise being overlooked is ridiculous,” said Miss Cannon, a contract assistant from Swaffham.

The women had gone for the 9pm to 10pm swim and left the pool at 9.50pm, an announcement asking everybody to leave was then made while the were changing but by 10.05pm they were stunned to find the centre completely closed with no staff left in the building.

“I really like the place and I am happy with everything else. But whoever was working there last week just did not care. I am just shocked about the security,” said Miss Cannon.

A spokesman for Norfolk Police said: “We received a call from one of the women at 10.22pm who said they were trapped in the sports complex. We tried to get hold of the key holder but in the end advised the women to leave via the fire exit. We then secured the premises.”

The centre opened in April and was built as part of a joint project between Parkwood Leisure, which runs the centre, and Breckland Council.

Joe Liggett, senior leisure manager at Breckland Council, said: “It should not have happened and given the seriousness of this matter we will be taking it up formally with Parkwood.

“The building is leased to Parkwood so they have operational control of the building. Unfortunately staff at Breckland Council were not able to give the ladies the numbers of the key holders.

“We have now put the right procedures in place to ensure this does not happen again.”

Claire Byles, manager of the centre, said that she was aware of what had happened and was investigating the incident.