Almost as swiftly as it arrived, the Banksy versus Bristol Museum exhibition has disappeared from the city.

De-rigging began at 5pm on Bank Holiday Monday – at the very moment the last visitor left the museum.

Under yet another cloak of secrecy, the exhibition was broken back up and shipped out of the city, on a series of anonymous lorries.

"Once the Banksy pieces are out, then we've had to tackle the enormous job of cleaning the place.

"The past 12 weeks have felt like a constant party, and the clean up very much has the feeling of the morning after when there's all the washing up to tackle," says Paul Barnett, acting head of Bristol's museum service.

"That means that we've had to close the museum entirely for two days while we clean right through and return those museum exhibits that we had to put into storage to make way for the Banksy pieces.

"The Banksy Effect will continue for the museum, because the show has brought lots of people in who have never been to the museum before, or who have not visited for years. I'm confident that now they've seen what a great attraction it is, they will want to come back to spend some time looking at our permanent collection.

"We also have a new temporary exhibition coming in next week, which is bringing together 11 international artists to demonstrate the rich works of art that can be produced in simple pencil drawings.

"So there is plenty to look forward to."

Councillor Simon Cook, the city council's deputy leader and cabinet member for culture, sport and capital projects, said there was no disabled access to 12 exhibits and said he will push for extra funding to incorporate new disabled access lifts into the parts of the building that wheelchair users could not reach.

Banksy may donate a piece from the show to stay at the museum permanently.

"It will be brilliant if he does give us something," says Paul Barnett. "But of course, the etiquette will not be for us to choose a piece – it will be for the artist to approach us in the next few weeks."