A Pizza Hut outlet was slapped with an immediate closure notice for public protection after inspectors found evidence of an "extensive and active" mouse infestation in the premises, a court has heard.
Environmental health officers found mouse droppings throughout the kitchen area of the Swansea property, as well as in the property's damp cellar where the pizza delivery boxes were stored.
The company that owns the franchise on St Helen's Road business has been fined £8,000.
Swansea Magistrates Court heard inspectors carried out a routine inspection of the pizza delivery and takeaway premises on March 13 last year.
Sarah Thyer, prosecuting for Swansea Council, said they found evidence of an "extensive and active" mouse infestation problem, with mouse droppings in the kitchen area, in the dough-proving machine, behind the pizza toppings fridge, and on a preparation table.
They also found food spillage and debris on the floor, and a dirty chiller with areas of encrusted grime.
The court heard that in the basement - where the empty pizza delivery boxes were being stored - the inspectors found black mould on the walls, and a dead mouse.
The prosecutor said the boxes were being stored in a way that "exposed them to contamination from rodent feaces".
Miss Thyer said the inspectors also found a lack of proper staff training, and a failure to register as a food operator.
The court heard the inspectors served an emergency prohibition notice on the premises - signifying an "immediate risk of injury to health" - and closed the business on the spot.
The prosecutor said premises were cleaned and disinfected the following day, and the company successfully applied for the prohibition notice to be lifted.
After a subsequent re-inspection of the premises it was award the highest hygiene rating of five.
The company that owns the franchise, Milton Keynes-based Sania PH Ltd, had previously pleaded guilty to six offences under the Food Hygiene Wales Regulations when the case came before district judge Neale Thomas sitting at the magistrates court.
Six mirror charges against the owner of the company, 44-year-old Mubarak Ali of Shirley Moor, Kents Hill, Milton Keynes, were dropped.
The court heard Mr Ali's businesses run a total of 18 Pizza Hut franchises - nine in Wales and nine in England.
Ieaun Rees, on behalf of the company said, said there had never been any problems with any of its outlets before, including the one it operated on Neath Road in Hafod, Swansea.
He said Mr Ali had inherited the situation at the St Helen's Road shop when he took over the franchise some six months before the inspection, and as soon as the problems were brought to his attention he had remedied them within 48 hours.
The district judge said the conditions in the takeaway had clearly been serious enough for the council to close it immediately - however, it was very much to the credit of Mr Ali's company that work to put right the problems was begun the day after the inspection.
With a one third discount for the guilty pleas the firm was fined £8,000 and given 56 days to pay.
